New starter - after help deciding between Takahashi FC-76DCU & FC-100DC

[Surfer Chris]

Thankyou again for your responses over the weekend.

Going to see what eyepieces I can find in stock today. 

Deadlake - just re-reading your comments above regarding maybe requiring a different mount for the 100DC at high powers. I guess this was part of the difficulty I was having between the choice of 76DCU & 100DC originally. I wondered if, in reality I would not be able to take advantage of the 'really high powers' that the 100DC can potentially offer on the lightweight Scopetech mount (I have heard 200x plus is fairly common). And therefore it may have been better to stick to the smaller 76DCU where I might be able to utilise the full possibilities of the scope in my desired mounting arrangement.

Presumably, even if the mount doesn't work well with the super high powers, I guess generally I will see a significant improvement going with the 100DC over the 76DCU for the 'average' powers? I am guessing if I went with the 76DCU I would typically be observing in the range of up to 150x max, and with the 100DC maybe up to 200x max? And for a given magnification (e.g. 100x), I am hoping the 100DC will give a crisper and brighter image with more resolution. So FC100-DC still a better choice even for the lower 'typical' magnifications. I hope that my understanding is correct!!!

On another matter, I was thinking of mounting a Tak Clamp directly onto the Scopetech Zero Mount (apparently you can do this). So I wouldn't have a dovetail bar and keep the weight down a little more. This would mean that I would be using the Takahashi Clamp to de-mount the scope and for adjusting balance etc. Do you think this is a bad idea? Would I be better to get a dovetail bar for balance adjustment? In this case I would then probably get and ADM clamp rather than using a single screw to hold the scope...I don't like the idea of a single screw point holding up such an expensive item.

[dweller25]

58 minutes ago, Surfer Chris said:

Thankyou again for your responses over the weekend.

Going to see what eyepieces I can find in stock today. 

Deadlake - just re-reading your comments above regarding maybe requiring a different mount for the 100DC at high powers. I guess this was part of the difficulty I was having between the choice of 76DCU & 100DC originally. I wondered if, in reality I would not be able to take advantage of the 'really high powers' that the 100DC can potentially offer on the lightweight Scopetech mount (I have heard 200x plus is fairly common). And therefore it may have been better to stick to the smaller 76DCU where I might be able to utilise the full possibilities of the scope in my desired mounting arrangement.

Presumably, even if the mount doesn't work well with the super high powers, I guess generally I will see a significant improvement going with the 100DC over the 76DCU for the 'average' powers? I am guessing if I went with the 76DCU I would typically be observing in the range of up to 150x max, and with the 100DC maybe up to 200x max? And for a given magnification (e.g. 100x), I am hoping the 100DC will give a crisper and brighter image with more resolution. So FC100-DC still a better choice even for the lower 'typical' magnifications. I hope that my understanding is correct!!!

On another matter, I was thinking of mounting a Tak Clamp directly onto the Scopetech Zero Mount (apparently you can do this). So I wouldn't have a dovetail bar and keep the weight down a little more. This would mean that I would be using the Takahashi Clamp to de-mount the scope and for adjusting balance etc. Do you think this is a bad idea? Would I be better to get a dovetail bar for balance adjustment? In this case I would then probably get and ADM clamp rather than using a single screw to hold the scope...I don't like the idea of a single screw point holding up such an expensive item.

@JeremyS used a dovetail on his scopetech Zero - it may be worth asking for his thoughts.....

[JeremyS]

Just now, dweller25 said:

@JeremyS used a dovetail on his scopetech Zero - it may be worth asking for his thoughts.....

Yes I use a dovetail. I’m not that worried about single attachment screw. It also means I can use the same OTA on different mounts, or different OTAs on the ScopeTech - attaching a Tak cradle would not allow that. I’m also not convinced that the Tak cradle direct attachment saves much space or weight. I’d actually be more concerned about clunking the OTA with the loose cradle clamp when mounting or dismounting the OTA, resulting in a scratch on the OTA. Especially when cold, or taking the scope inside when rain starts unexpectedly as it did the other night - and I’m a bit cackhanded anyway 😊

[John]

1 hour ago, Surfer Chris said:

Thankyou again for your responses over the weekend.

Going to see what eyepieces I can find in stock today. 

Deadlake - just re-reading your comments above regarding maybe requiring a different mount for the 100DC at high powers. I guess this was part of the difficulty I was having between the choice of 76DCU & 100DC originally. I wondered if, in reality I would not be able to take advantage of the 'really high powers' that the 100DC can potentially offer on the lightweight Scopetech mount (I have heard 200x plus is fairly common). And therefore it may have been better to stick to the smaller 76DCU where I might be able to utilise the full possibilities of the scope in my desired mounting arrangement.

Presumably, even if the mount doesn't work well with the super high powers, I guess generally I will see a significant improvement going with the 100DC over the 76DCU for the 'average' powers? I am guessing if I went with the 76DCU I would typically be observing in the range of up to 150x max, and with the 100DC maybe up to 200x max? And for a given magnification (e.g. 100x), I am hoping the 100DC will give a crisper and brighter image with more resolution. So FC100-DC still a better choice even for the lower 'typical' magnifications. I hope that my understanding is correct!!!

On another matter, I was thinking of mounting a Tak Clamp directly onto the Scopetech Zero Mount (apparently you can do this). So I wouldn't have a dovetail bar and keep the weight down a little more. This would mean that I would be using the Takahashi Clamp to de-mount the scope and for adjusting balance etc. Do you think this is a bad idea? Would I be better to get a dovetail bar for balance adjustment? In this case I would then probably get and ADM clamp rather than using a single screw to hold the scope...I don't like the idea of a single screw point holding up such an expensive item.

I use a Vixen type dovetail bar bolted (2 bolts) onto the tube clamp to hold my FC100-DL. It is not heavy and it does make adjusting the position of the tube easy, should you need to do it. Some people use tube rings and a dovetail bar but the tube diameter of the FC100's is 95mm which is quite hard to find rings for. IMHO the clamp plus DT bar does a good job anyway.

100mm is, IMHO, preferable over 76mm even at lower magnifications. More resolution and light grasp is beneficial even at lower powers. 

BUT ...... portability is not such an issue for me and my mounts are heavier duty than the Scopetech I think.

 

[John]

Just a further thought.

Both the 100mm and 76mm Taks are superb scopes in their aperture of course.

It's easy for us to urge you in the direction of the 100mm for lots of good reasons but at the end of the day it's your money and the way you want to approach the hobby that matters most and I would not feel easy if we pushed you into a decision that you were not ultimately comfortable with.

If the smaller, lighter, easier to mount scope will get used more, that's the one to go for

[Stu]

@Surfer Chris, I just remembered this thread I started with info on the Scopetech Zero. It includes a video of the internationally recognised ‘Stu Standard Tap Test’ 🤣, designed to show how longer vibrations take to damp down. Even with the ScopeTech 80mm f15 onboard it copes well.

 

[Surfer Chris]

Since I am looking to have only one scope, interchangeability between scopes and mounts wasn't really a worry for me - hence I thought I could do away with the dovetail bar and just use the Tak clamp itself for de-mounting and balance adjustment.

I was also originally thinking of keeping the scope and mount/tripod set-up at all times, and just lifting the entire set-up though our dining room doors onto the garden patio as and when necessary. However, with the FC100-DC costing £2k I am wondering if I should be thinking of actually carrying tripod and scope separately...especially as there are two steps down from the dining room door onto the patio outside (its about a 18" step down). Tripping on these steps whilst lifting the entire set-up would be devastating! May be best to make a nice wooden case for the OTA (to keep it safe and away from the kids!), and just keep the tripod and mount set-up and ready to accept the OTA as and when needed.

If I do end up frequently carrying out in two loads - I am thinking a dovetail might be a safer bet, making it less likely that I ding the tube on the edges of the open Tak clamp...which is along the lines of your reason Jeremy. So I think a dovetail is probably a sensible choice for the little extra money and extra weight.

John - don't put that doubt back in my head! From my thoughts immediately above about the potential risks of carrying the expensive 100DC OTA and tripod out in one go - I am already worrying again if the 76DCU would give me more confidence in handling and moving around as one complete unit.

Jeremy - What I should have perhaps asked the other day...when not travelling, how much do you actually use your 76DCU compared to the FC-100? Do you always pick the FC-100 when at home?

 

[JeremyS]

51 minutes ago, Surfer Chris said:

Since I am looking to have only one scope, interchangeability between scopes and mounts wasn't really a worry for me - hence I thought I could do away with the dovetail bar and just use the Tak clamp itself for de-mounting and balance adjustment.

I was also originally thinking of keeping the scope and mount/tripod set-up at all times, and just lifting the entire set-up though our dining room doors onto the garden patio as and when necessary. However, with the FC100-DC costing £2k I am wondering if I should be thinking of actually carrying tripod and scope separately...especially as there are two steps down from the dining room door onto the patio outside (its about a 18" step down). Tripping on these steps whilst lifting the entire set-up would be devastating! May be best to make a nice wooden case for the OTA (to keep it safe and away from the kids!), and just keep the tripod and mount set-up and ready to accept the OTA as and when needed.

If I do end up frequently carrying out in two loads - I am thinking a dovetail might be a safer bet, making it less likely that I ding the tube on the edges of the open Tak clamp...which is along the lines of your reason Jeremy. So I think a dovetail is probably a sensible choice for the little extra money and extra weight.

John - don't put that doubt back in my head! From my thoughts immediately above about the potential risks of carrying the expensive 100DC OTA and tripod out in one go - I am already worrying again if the 76DCU would give me more confidence in handling and moving around as one complete unit.

Jeremy - What I should have perhaps asked the other day...when not travelling, how much do you actually use your 76DCU compared to the FC-100? Do you always pick the FC-100 when at home?

 

I wouldn’t consider carrying my FC76 DCU mounted on the Report tripod. Too many things to go wrong.

If you are worried about the screw on the dovetail, I think you can get ADM dovetail clamps to fit the ScopeTech mount.

I really don’t use my FC 76 that much when I am not travelling, especially by air (I took it with me to India last year when I was on a 3 month work assignment). By car it’s less of a deal - in fact the FC 100 DZ doesn’t take up much more room, which is why I decided to get it in addition to the 76.

[Surfer Chris]

Ok - that's interesting Jeremy. I perhaps thought that it would be common to try an lift these sort of set-ups out in one go. You are saying you wouldn't even lift the 76DCU out whilst mounted.

Sad that I am, I have got the tripod from my old cheap 90's Tasco reflector out and loaded it up with some weight to approximate the weight of both scopes mounted on a tripod. Even with the approx. mounted weight of the 76DCU (around 9kg with tripod and mount), although it feels OK to carry about laterally on a level floor indoors, it is still weighty enough to make me feel that if I was to try and lift this up and over the door threshold, through the doors and down the two steps onto the patio (in the dark) - that would be a little nerve racking. Think the 100DC will be about 10kg with tripod and mount.

[JeremyS]

45 minutes ago, Surfer Chris said:

Ok - that's interesting Jeremy. I perhaps thought that it would be common to try an lift these sort of set-ups out in one go. You are saying you wouldn't even lift the 76DCU out whilst mounted.

Sad that I am, I have got the tripod from my old cheap 90's Tasco reflector out and loaded it up with some weight to approximate the weight of both scopes mounted on a tripod. Even with the approx. mounted weight of the 76DCU (around 9kg with tripod and mount), although it feels OK to carry about laterally on a level floor indoors, it is still weighty enough to make me feel that if I was to try and lift this up and over the door threshold, through the doors and down the two steps onto the patio (in the dark) - that would be a little nerve racking. Think the 100DC will be about 10kg with tripod and mount.

For me it’s not the weight (I could lift the Tak FC 76 DCU + ScopTech + Berlebach Report with one hand). It’s more the concern of knocking a tripod leg or OTA as I am manoeuvring through doors esp in the dark- not worth the risk.

However I have no problem lifting  the whole assembly out through the patio doors and onwards a few steps. The aperture is wide if both French doors are open, there is only one step down, and the patio is flat with no trip hazards. 
 

And I’ve done the same once or twice with the FC 100 DZ.

But opening the Patio doors lets all the heat out, so my usual route in winter is via the laundry room, which is longer, more torturous and full of other hazards, like hanging clothes to get snagged on, wellies piled by the back door etc 🤣

It’s a matter of assessing the risks and deciding which to accept.

[Surfer Chris]

One thing I meant to ask the other day, when trying to determine what the views might be like for both the FC100DC and FC76DCU, I came across a couple of videos which seem to show views of Saturn through both scopes;

https://www.youtube.com/watch?v=GOHHUxZWT4U

https://www.youtube.com/watch?v=0A7MHrd5ppk

The first video is using the FC-76DCU and live view of Saturn is shown from around 5:15 minutes into the video.

Second video is using a FC-100DF, and live view of Saturn about 2:15 into the video.

For those of you who have used both 76DCU and FC-100, is this a fair comparison of the difference in views between these scopes? With these videos, the FC-100DF does looks significantly better than the FC-76...but not sure if that is just because the 76DCU is being used on a day of worse seeing? And perhaps the 76DCU is being pushed a bit high on the magnification front?

[Stu]

32 minutes ago, Surfer Chris said:

One thing I meant to ask the other day, when trying to determine what the views might be like for both the FC100DC and FC76DCU, I came across a couple of videos which seem to show views of Saturn through both scopes;

https://www.youtube.com/watch?v=GOHHUxZWT4U

https://www.youtube.com/watch?v=0A7MHrd5ppk

The first video is using the FC-76DCU and live view of Saturn is shown from around 5:15 minutes into the video.

Second video is using a FC-100DF, and live view of Saturn about 2:15 into the video.

For those of you who have used both 76DCU and FC-100, is this a fair comparison of the difference in views between these scopes? With these videos, the FC-100DF does looks significantly better than the FC-76...but not sure if that is just because the 76DCU is being used on a day of worse seeing? And perhaps the 76DCU is being pushed a bit high on the magnification front?

It’s been a while since I had the 76, and never did a side by side but it seems fairly realistic. Resolution is directly related to aperture, so the 100 will have about 30% better resolution.

I think John and I differ a little in our views in that I still get rewards from using smaller scopes, and enjoy the increased portability and convenience. That said, I now have 3 4” scopes (TV Genesis, FC100DC and a Vixen FL102S) and they are definitely where planetary observing starts to get interesting, particularly the latter two, rather than challenging ie the detail is more easily visible. Lunar and doubles with a smaller scope are great fun, as is widefield DSO observing under a good sky but I would tend to agree that you need 4” to really enjoy planetary observing. Others may disagree of course, trouble is we are all different so can only ever give a personal perspective.

[JeremyS]

1 hour ago, Surfer Chris said:

One thing I meant to ask the other day, when trying to determine what the views might be like for both the FC100DC and FC76DCU, I came across a couple of videos which seem to show views of Saturn through both scopes;

https://www.youtube.com/watch?v=GOHHUxZWT4U

https://www.youtube.com/watch?v=0A7MHrd5ppk

The first video is using the FC-76DCU and live view of Saturn is shown from around 5:15 minutes into the video.

Second video is using a FC-100DF, and live view of Saturn about 2:15 into the video.

For those of you who have used both 76DCU and FC-100, is this a fair comparison of the difference in views between these scopes? With these videos, the FC-100DF does looks significantly better than the FC-76...but not sure if that is just because the 76DCU is being used on a day of worse seeing? And perhaps the 76DCU is being pushed a bit high on the magnification front?

Setting aside the bizarre aspects of the first video 🤣, as Stu says it’s fairly realistic- or at least relatively between the 76 and 100. Under the same conditions, the 100 will always be better. If you foresee an interest in planetary observing, the FC 100 is the one to go for.

But I think you’ve ordered the FC 100 anyway, right?

[Surfer Chris]

Yes I have ordered the FC-100. 

I had asked the supplier to hold it until I got back to them regarding eyepieces etc (as in I had stuff to add to order which could have been shipped together). But their shipping department is obviously super efficient - and the scope arrived yesterday! To be fair to them they have been really good and very tolerant to my many technical questions.

However, I am scared to open it! After re-evaluating my eyepiece selection etc...the price has gone up a fair bit, so although I am desperate to have the better views of the larger scope - feeling a little nervous about committing to the full £4k the package is now looking to cost. 76DCU would be around £3k which seems a lot more in line with my original spending expectations.

Over the long term £4k is not much - as Mike said, some people pay £1000+ per year for golf fees alone. But just wondering if I should have gone with the smaller for now with a view to upgrade a couple of years down the line? With two young kids, and a possibility of moving house in the next year, spending £4k on myself seems a little selfish. I did buy the other half a new laptop on the weekend though - perhaps could use that fact to soften the blow of the £4k spend??? 

Annoyingly I spotted a Pentax 10XW eyepiece on Astrobuysell that I just missed out on for £180. That could have helped get my eyepiece costs down a little.

🤦‍♂️

[Surfer Chris]

Another video from the same guy shows side-by-side images. But I suspect these are stacked images maybe - and therefore appear a little clearer than you would expect to see directly through the scope? If I did see images like either of these though (for 100 & 76) - I would be happy enough!

[Surfer Chris]

Well I just opened the Scopetech Mount - and it does look very nice! Feels nice and rigid in the hand.

[JeremyS]

You did incredibly well to lay your hands on a Tak FC 100. I thought they were out of stock everywhere 

Pics please!

[dweller25]

2 hours ago, Surfer Chris said:

Yes I have ordered the FC-100. 

I had asked the supplier to hold it until I got back to them regarding eyepieces etc (as in I had stuff to add to order which could have been shipped together). But their shipping department is obviously super efficient - and the scope arrived yesterday! To be fair to them they have been really good and very tolerant to my many technical questions.

However, I am scared to open it! After re-evaluating my eyepiece selection etc...the price has gone up a fair bit, so although I am desperate to have the better views of the larger scope - feeling a little nervous about committing to the full £4k the package is now looking to cost. 76DCU would be around £3k which seems a lot more in line with my original spending expectations.

Over the long term £4k is not much - as Mike said, some people pay £1000+ per year for golf fees alone. But just wondering if I should have gone with the smaller for now with a view to upgrade a couple of years down the line? With two young kids, and a possibility of moving house in the next year, spending £4k on myself seems a little selfish. I did buy the other half a new laptop on the weekend though - perhaps could use that fact to soften the blow of the £4k spend??? 

Annoyingly I spotted a Pentax 10XW eyepiece on Astrobuysell that I just missed out on for £180. That could have helped get my eyepiece costs down a little.

🤦‍♂️

You could perhaps keep the 4” and go for less expensive eyepieces for now and slowly upgrade later when funds allow.....

Edited February 10, 2021 by dweller25

[Surfer Chris]

 

Haven't opened the box yet Jeremy! That was my thought a short while ago David - what could I do in the short term to keep the eyepiece costs down - then acquire decent used ones as and when they come along?

The latest plan was to go with;

24mm Panoptic ~£306

4mm or 5mm Delite £243

11mm or 15mm Delite ~£243

But I think the above is keeping my EP selection fairly limited. And don't see much scope for trimming costs out short term.

[KP82]

2 hours ago, Surfer Chris said:

Yes I have ordered the FC-100. 

I had asked the supplier to hold it until I got back to them regarding eyepieces etc (as in I had stuff to add to order which could have been shipped together). But their shipping department is obviously super efficient - and the scope arrived yesterday! To be fair to them they have been really good and very tolerant to my many technical questions.

However, I am scared to open it! After re-evaluating my eyepiece selection etc...the price has gone up a fair bit, so although I am desperate to have the better views of the larger scope - feeling a little nervous about committing to the full £4k the package is now looking to cost. 76DCU would be around £3k which seems a lot more in line with my original spending expectations.

Over the long term £4k is not much - as Mike said, some people pay £1000+ per year for golf fees alone. But just wondering if I should have gone with the smaller for now with a view to upgrade a couple of years down the line? With two young kids, and a possibility of moving house in the next year, spending £4k on myself seems a little selfish. I did buy the other half a new laptop on the weekend though - perhaps could use that fact to soften the blow of the £4k spend??? 

Annoyingly I spotted a Pentax 10XW eyepiece on Astrobuysell that I just missed out on for £180. That could have helped get my eyepiece costs down a little.

🤦‍♂️

At f/7.4 it's unlikely you will notice a big difference between premium eyepieces and the more economical ones.

If I were in your position, I'd keep the FC100 and get myself a set of BST starguiders to start with, then gradually upgrade them to TV, Nikon or Pentax if I must have the best. Your financial loss will be a lot less this way than getting the 76DCU and later on sell it to fund the FC100.

[Surfer Chris]

Thanks for the suggestion KP82. I hadn't even looked at those EP's. 

That would bring the package price down to £3300. Sounds much better.

So the question is now...would something like FC-100DC + BST Starguiders still give superior performance over the 76DCU + Televue EP's?

[JeremyS]

3 minutes ago, Surfer Chris said:

Thanks for the suggestion KP82. I hadn't even looked at those EP's. 

That would bring the package price down to £3300. Sounds much better.

So the question is now...would something like FC-100DC + BST Starguiders still give superior performance over the 76DCU + Televue EP's?

Yes

But you could always buy used high q eyepieces (TV, Pentax etc) along the way, as budget allows

[Stu]

7 minutes ago, Surfer Chris said:

Thanks for the suggestion KP82. I hadn't even looked at those EP's. 

That would bring the package price down to £3300. Sounds much better.

So the question is now...would something like FC-100DC + BST Starguiders still give superior performance over the 76DCU + Televue EP's?

Yes it would, the resolution benefits will still show clearly, and the BSTs have a very good reputation. Often people put very good eyepieces in less good scopes which seems a waste, better to have a excellent scope to start with and build the eyepieces as you go along.

[Surfer Chris]

Yes that was the thought Jeremy. If the FC-100 with cheap EP's will still be better than 76DCU with Televue's...then get a small set of these BST eyepieces to keep me going - then keep a good eye out for decent used EP's along the way....or buy new decent ones as and when I feel more relaxed about finances. And also when I have had a chance to see how much I am using the scope and how I get on with certain mags/FOV etc.

[Deadlake]

On 08/02/2021 at 09:11, Surfer Chris said:

Thankyou again for your responses over the weekend.

Going to see what eyepieces I can find in stock today. 

Deadlake - just re-reading your comments above regarding maybe requiring a different mount for the 100DC at high powers. I guess this was part of the difficulty I was having between the choice of 76DCU & 100DC originally. I wondered if, in reality I would not be able to take advantage of the 'really high powers' that the 100DC can potentially offer on the lightweight Scopetech mount (I have heard 200x plus is fairly common). And therefore it may have been better to stick to the smaller 76DCU where I might be able to utilise the full possibilities of the scope in my desired mounting arrangement.

Presumably, even if the mount doesn't work well with the super high powers, I guess generally I will see a significant improvement going with the 100DC over the 76DCU for the 'average' powers? I am guessing if I went with the 76DCU I would typically be observing in the range of up to 150x max, and with the 100DC maybe up to 200x max? And for a given magnification (e.g. 100x), I am hoping the 100DC will give a crisper and brighter image with more resolution. So FC100-DC still a better choice even for the lower 'typical' magnifications. I hope that my understanding is correct!!!

On another matter, I was thinking of mounting a Tak Clamp directly onto the Scopetech Zero Mount (apparently you can do this). So I wouldn't have a dovetail bar and keep the weight down a little more. This would mean that I would be using the Takahashi Clamp to de-mount the scope and for adjusting balance etc. Do you think this is a bad idea? Would I be better to get a dovetail bar for balance adjustment? In this case I would then probably get and ADM clamp rather than using a single screw to hold the scope...I don't like the idea of a single screw point holding up such an expensive item.

I wouldn't be put off by this, if you have one scope a 100 mm refractor is the one to have for many reasons. I have a ADM mount and extended vixen dovetail now, I can give it another go when the moon next comes up. Not been using the ScoepTech as much due to having a new SXP2 mount to use.

When I was mentioned high magnification I meant 300-400x, around 200x will be fine.