Eye piece advise for 300p

[Barry-W-Fenner]

57 minutes ago, bomberbaz said:

Post up a picture taken through the focuser tube, let us have a look. A 2nd eye looking things over may see thing your maybe over looking. Just a suggestion.

Will do Steve, the more eyes the merrier appreciate the assistance. 👍

[Don Pensack]

5 hours ago, Barry-W-Fenner said:

Hi Don,

Thanks for the insightful post regarding the primary mirror, It would seem that you have forgotten more about mirrors than I will ever know 🙂 Are you in the optics profession?

So it would appear that i have collimated to a mechanical state by going over the usual processes. How would one know how to collimate to a optical state?

Reference the 3 Cs I think the scope was out for about an hour on each occasion cooling. Perhaps i am not giving the scope the required amount of time to cool down enough. It might explain why the moon looked great at 6am as I left the scope out from my 3am viewing session.

Thanks for your assistance, Much appreciated.

Baz

 

Optical collimation is aligning the optical axes: focuser axis (using a laser or a sight tube crosshairs), and primary mirror axis (using a Cheshire, a collimation cap, or a barlowed laser).

Mechanical collimation is centering the secondary under the focuser and getting it rotated perfectly.  Neither is essential for optical collimation.  And it is optical collimation that yields the best images.

Fans will help cool the mirror and give those morning images earlier in the night.

As for being in the business, yes, I am--since 2005.  But I've been an amateur astronomer since 1963.

[bomberbaz]

4 minutes ago, Louis D said:

I just avoid going out on nights with significant particulate matter in the air, like on night of the 4th of July (fireworks residue), when my neighbors are burning logs in their fireplaces, backyard grilling, or are running their smokers overnight.  The rest of the time, the level of airborne particulates hasn't been much of an issue for me.

Ah but you live in texas Louis, not in the UK where in my town there are many air pollutants at not that great a distance from my home.  Basically our population density is quite high and thus air polution will naturally be higher. Hence my statement. 

Cheers

Steve

[Don Pensack]

3 hours ago, Louis D said:

I cool mine straight up and down like a chimney.  I don't know what advantage tilting it would provide.

DEW.  It will form on a mirror pointed at the sky, but not on a mirror pointed at trees or buildings.

It will affect the secondary first, but also the primary.

Now, if you have fans, the scope can be horizontal and still cool just as well without risk of dew.

[Louis D]

18 hours ago, Don Pensack said:

DEW.  It will form on a mirror pointed at the sky, but not on a mirror pointed at trees or buildings.

It will affect the secondary first, but also the primary.

Now, if you have fans, the scope can be horizontal and still cool just as well without risk of dew.

Never had that issue in Texas, not even on my 127 Mak.  Perhaps because I don't observe in the mornings when the air temperature is closer to the dewpoint.  I've never felt the slightest need for dew strips or shields.

[Don Pensack]

2 hours ago, Louis D said:

Never had that issue in Texas, not even on my 127 Mak.  Perhaps because I don't observe in the mornings when the air temperature is closer to the dewpoint.  I've never felt the slightest need for dew strips or shields.

I don't have much of an issue in southern California, either, but when I was last observing in Australia the dew at the site was so heavy it filled a table with a lip on the edge with a pool of water, and all the dobs had to use hair dryers on the secondaries just to keep them usable.  I usually observe all night when I go out, so I run into dew a lot, though it isn't heavy here.  Where I grew up, the morning dew was so heavy it wetted everything as if it had rained.   There are some wet environments out there.

[Barry-W-Fenner]

Hi all.

Just managed to get a couple of shots down the focuser tube. Not the best as the scope is tucked up in the corner of the utility room at the moment so not much room to extend and manoeuvre the tube about. I just though I would try to show the currwnt alignment of the mirrors. Maybe there is something obvious to those more experienced than I!

when I have the scope out cooling for its next outing I will attempt some better pics.

😀 Baz

[Ricochet]

You need to take the photo through the Cheshire. 

[bomberbaz]

Yeah sorry Baz I shoulda said take the picture through cheshire, my bad.

[Barry-W-Fenner]

OK chaps, I will see if I can get a decent shot tomorrow.

👍

[Barry-W-Fenner]

Hi gents,
Not sure if these picks through my cheshire are of much help. Taken in the cramped corner of my utility room again.

I hope to get some better shots when I actually manage to get the scope out again next time..

 

 

[John]

If it's off, it's not far off at all.

 

 

[Barry-W-Fenner]

14 minutes ago, John said:

If it's off, it's not far off at all.

 

 

Thanks John.

I hope to get the scope out over the coming nights, give it a collimation, a good cool down and do some viewing. It's been a long time coming.

it's my 1st summer in the hobby and I didn't realise viewing time would be so scarce this time of year. Obviously I knew it would get dark much later but the weeks of cloud have been unbelievable. I feel like I bought the 300p right at the wrong time.

I'm getting the penny's together to purchase a Morpheus eye piece, ideally one I can barlow to give two focal lengths. I'm in a predicament as to which size to go for 17.5, 14 or 12.5mm

I am thinking the 12.5 so I can barlow down to around 6mm. This gives me a size between my bst 5mm & 8mm. However I do have a 12mm bst.

the 14 would give me a 7mm also. But again I have the 15mm & 8mm bst so would it be worth it 🤔🤔🤔

Thoughts welcome

 

Baz

[bomberbaz]

55 minutes ago, John said:

If it's off, it's not far off at all.

 

 

what he said

[bomberbaz]

I think get the 14mm Baz. That barlows to a very useful 7 a tad over x200, the 12.5 barlowed is going to x240 and will be used less. You will end up getting a 17.5 morpheus as well. In conjunction with a decent barlow that will give you a really good cover over mid and high range magnifications. 

PS, then get the 12.5 as well. You will end up selling all the bst's, lol 

[Barry-W-Fenner]

12 hours ago, bomberbaz said:

I think get the 14mm Baz. That barlows to a very useful 7 a tad over x200, the 12.5 barlowed is going to x240 and will be used less. You will end up getting a 17.5 morpheus as well. In conjunction with a decent barlow that will give you a really good cover over mid and high range magnifications. 

PS, then get the 12.5 as well. You will end up selling all the bst's, lol 

Hi Steve,

Thanks for this info, I have been a bit stuck trying to decide which will be  the best size to go for out of the 3 mid power focal lengths. Unfortunately which ever way I go I am going to overlap slightly somewhere. As you say though the 14mm will give me a 7mm also and drop in just below my 15mm & 8mm BST range. @John mentioned that the [removed word] in the armour of the BST range was no eye piece in the 6-7mm region and he is correct, I have been lacking an eye piece that gives me around x200 and your advice on  the 14mm Morpheus should cover now cover this. Providing of course my BST x2 barlow is up to the challenge!

You are probably correct, In time I may consider purchasing more of the Morpheus range which would suit both my 300 & 200p

Thanks Steve 🙂

 

Baz

 

[Barry-W-Fenner]

Coming back to collimation with a Cheshire, just wanted to run through it to make sure I am not being a total lemon and doing it incorrectly.

I put the cheshire in the focuser with the 45 degree angle facing down towards the primary.

after this I have got all 3 primary clips roughly equal when viewing down the Cheshire, note I do this with the focuser fully in.

once this is done I have got the little spot centered in the ring on the primary mirror.

my main question is, what is the purpose of the crosshairs? In my 300p they are very faint and slightly off center. Would this be correct or should they be dead center.

Thanks again for being patient with me folks, as I said I can be a bit of a lemon 😁😁

Baz

[Pixies]

The 45 degree angle faces towards the light, so that it's illuminated when you look down it and the dot and cross hairs are easier to see.

 

[Ricochet]

50 minutes ago, Barry-W-Fenner said:

after this I have got all 3 primary clips roughly equal when viewing down the Cheshire, note I do this with the focuser fully in.

Ignore the mirror clips. Align the doughnut in the centre of the primary mirror with the cross hairs at the bottom of the cheshire/sight tube by adjusting the secondary. You should do this with the focuser extended to roughly the same position that is required to focus eyepieces. 

52 minutes ago, Barry-W-Fenner said:

my main question is, what is the purpose of the crosshairs? In my 300p they are very faint and slightly off center. Would this be correct or should they be dead center.

When you say off centre, are they not pointing at the doughnut, or are they not centred in the cheshire? If you rotate the cheshire in the focuser, do the cross hairs stay pointing at the same spot or do they prescribe a circle? 

[Barry-W-Fenner]

Thank you Ricochet, I will check all of the above when I set up tonight.

I did some viewing from 10pm to 12am last night, I let the scope cool for a good two hours before use. Stars looked much better than previously. I had a look at a number of targets and they were all very clear in the 8 & 12mm bst,s

I got back out at 4am after a few hours kip to see Mars. It looked amazing with my 5mm & 8mm bst,s a very clear phase with different shade of colour to the planet. The southern ice caps stood out extremely well. They are a very appealing characteristic of Mars to view.

regards

Baz

[Don Pensack]

Here is a simple tutorial on the use of a Cheshire/sight tube combination (what you own).

Hint: pay no attention to the distant reflection of the crosshairs--only use the ones near your eye for collimation.

revised combination tool.pdf

[Barry-W-Fenner]

Hi all.

Hope all is well 🙂

Quick update, I have now received my 14mm Morpheus and viewed some excellent targets old and new! over the last two nights. I intend to do a report on this shortly, However I have a couple of questions regarding the eye piece itself.

1st a brief rundown.

I have been solely been using this eye piece to get a feel for it so all my observing over the last two nights have been at x107 or barlow'ed to x214

viewing the moon at x107 while dusky has been absolutely beautiful, I can get the whole moon nicely into the full field and it is clear from edge to edge. The detail is some of the best I have seen. Extremely clear and subtle details seem to pop out at you.   My BST barlow was a different story, The view at 214 was very blurry which I think was down to the seeing conditions to be fair, Everything was also wobbly at this power.

Stars loo wonderful, The big boys Such as Vega all looked like a beautiful and colourful point of light. The wide field is very impressive at giving a great view of background stars that really do immerse you. My 8yr old daughter really impressed me when she stepped up to the eye piece to view Vega and said " Dad you can see such a wide area in this eye piece and so much sky and stars"  she inst really into astronomy but picked up on the FOV straight away. my only slight "issue" has been stars do seem to start losing shape slightly towards the edge. True be told I am starting to wonder if this is my eyes rather than the optics?

 

So my questions regarding the Morp are:-

Regarding the eye cup. I assume you all use the standard fold up version for general viewing? I am still getting to grips with eye placement on this eye cup and am finding I need to be more precisely placed than on my BSTS which have a flat eye cup for me to dump my eye ball against 🙂 This is going to take a bit of getting used to on my part but any techniques or advice regarding eye placement welcome. I believe the eye cap with the side shield is for bino viewing only?

Also can the metal adapter be used to adjust the position of the eye cup at all for comfort? I read that it can help with eye relief but is predominantly to attach the eye piece to cameras and imaging equipment.

I am using the eye piece in the 1.25" adapter. Would there be any benefit to using it as a 2" eye piece? If not I dont really understand why the eye piece suits both barrel sizes, Maybe just convenience?

I bought the 14mm with the intention of using my barlow to give a higher power. However so far i have not had great viewing results in this configuration. I believe this is down to conditions but am wondering if this is more down to my x2 BST barlow not wanting to plat with the morp?  Truthfully I am not a huge fan of barlowing anyway. I personally don't like adding another weighty lense to the optical train. Which is actually a bit of an issue itself now. The combined weight of the morp and barlow do make my scope top heavy now and staying on target is difficult.  I thing I will be reverting to my 8mm BST for a bit more power until I can afford the 9mm Morp to get x166? Another thing with the barlow is it is making my optical train very long probably around 12-14 inches!

 

Any advise on the above appreciated. 🙂

Baz

 

 

 

 

 

 

 

 

 

[Geoff Barnes]

Hi Barry, if I was in your shoes and (like me) you love the Morpheus EP's, I would get the 6.5mm Morph. Getting the 9mm when you already have the BST 8mm doesn't seem to make a lot of sense. My 6.5mm in the 12 inch Dob is superb.

I have a decent barlow, the Celestron Ultima 2x Japanese one and I don't like the dimmer image it produces much, so I hardly ever use it these days.

[John]

You can use the extension piece to move the eye cup a bit further away from the eye lens which might help with eye positioning Barry. Try it and see.

I didn't get on with those "winged" eye cups but some people like them.

The Morpheus is a 1.25" eyepiece. Some folks prefer using these larger eyepieces in a 2 inch fitting because they feel more secure which is why some have a hybrid barrel design.

I would guess that the BST Barlow is the weak link in the optical train compared with the Morpheus optics.

 

 

[Barry-W-Fenner]

1 hour ago, Geoff Barnes said:

Hi Barry, if I was in your shoes and (like me) you love the Morpheus EP's, I would get the 6.5mm Morph. Getting the 9mm when you already have the BST 8mm doesn't seem to make a lot of sense. My 6.5mm in the 12 inch Dob is superb.

I have a decent barlow, the Celestron Ultima 2x Japanese one and I don't like the dimmer image it produces much, so I hardly ever use it these days.

Hi Geoff,

That's an interesting point. I did also think the 9mm might be a bit to close to my BST 8mm. My thinking was that my 8mm is my "go to" eye piece and the 9mm Morph would compliment this and perform better that the 8mm in the 300p? I would imagine I would then be covered for a good range of targets with the 8,9 & 14mm eye pieces - x187 x167 x107

You have now got me thinking about the6.5mm as an option. I thought this might be a bit to much power to use on a regular basis though as the sky quality here is worse than yours no doubt.  I imagine it does perform very well in the 300p, How often do you get to use the 6.5?

you have got me thinking now 🙂

 

57 minutes ago, John said:

You can use the extension piece to move the eye cup a bit further away from the eye lens which might help with eye positioning Barry. Try it and see.

I didn't get on with those "winged" eye cups but some people like them.

The Morpheus is a 1.25" eyepiece. Some folks prefer using these larger eyepieces in a 2 inch fitting because they feel more secure which is why some have a hybrid barrel design.

I would guess that the BST Barlow is the weak link in the optical train compared with the Morpheus optics.

Thanks for confirming this John, I am going to attach the extension straight after writing this as the Morph is sitting on my desk looking at me 🙂

I must admit I did find this type of eye cup quite fussy and I need to adjust my head position quite frequently. I will continue to use it and see how I get on. The views are very good once I have managed to get a comfortable viewing position.

Thanks for also confirming that this is in fact a 1.25 barrel with the option to adapt to 2" if required.

I was also thinking that the BST barlow could be the cause of not particularly good views. Its a shame as I was hoping to have "two" eye pieces for the price of one. I will give it another try tonight and see if conditions had any part to play? However I am only barlowing to a power of 214 so in theory it should have been ok. 

What would be a good performing barlow for this type of eye piece?

 

Thanks gents.

Baz