Rowan AZ75 - Stu’s thoughts

[John]

If you have slow motion controls then you can choose not to use them when you don't need / want them. If they are not fitted then you don't have that option.

I guess you can't blame folks for hoping for as many options as possible for their £550 even if the reality is that you can't get the level of engineering precision that Rowan provide AND all the bells and whistles for that price ?

 

 

Edited October 19, 2021 by John

[Alan White]

4 minutes ago, John said:

If you have slow motion controls then you can choose not to use them when you don't need / want them. If they are not fitted then you don't have that option.

I guess you can't blame folks for hoping for as many options as possible for their £550 even if the reality is that you can't get the level of engineering precision that Rowan provide AND all the bells and whistles for that price ?

Indeed John.
And I doubt anyone else could provide quality at that price point either.

 

[JeremyS]

8 hours ago, Stu said:

Just revisiting the whole slow motion debate, it’s interesting how preferences change over time @John. Reading back over previous posts, you have very much been an advocate of manual Dobs and alt Az mounts in the past, and their ability to track at high powers, whilst being fairly ambivalent about slow motion controls. I’m guessing that since the T-Rex you are now more of a convert?

It’s also interesting how this debate seems to be ALL about high power planetary observing when there is so much more to astronomy than that. A lot of DSO observing is done at lower powers, and having a lightweight mount which is easy to get to dark sites is definitely a benefit. The encoders (for those that want them) will make for very enjoyable and easy object finding.

That said, I do hope we can move beyond the slo mo/no slo mo debate which has been well covered, and focus on what the mount actually is, rather than what it is not.

At the risk of prolonging the SLO mo discussion….

in the past I was not that bothered about having SLO mos. Partly because the ones I’d used before weren’t that good, so I could take or leave. And if I wanted to do high mag planetary work, I would get out the AZEQ 6.

So what changed? Well, quite simply it was the arrival of the great AZ100. The SLO mos were so smooth and easy to use, I hardly bother to get out the AZEQ these days.

So learning that the AZ75 would even come with them as an option came as something of a shock and seemed a retrograde step.

However, I now see my reaction was irrational in the absence of  any data on how the new mount would actually work. @Stu’s Jupiter videos the other day have provided much reassurance. I will endeavour to keep an open mind whilst @Stu and @Alan White carry out their tests and report their findings.

ps apologies that my iPad capitalises SLO 

Edited October 19, 2021 by JeremyS

[StarryEyed]

There clearly is an opportunity for Rowan to consider two versions one with and one without you make your choice and pay accordingly. This being a prototype after all, its testing the design and the reaction to it. Product placement in a market place is a difficult thing to get right. A lighter smaller AZ100 might not be so dissimilar in price to a AZ100 or maybe that increases in price to make space, but its another option for customers. The process can take time. So lets hope things can move along quickly and smoothly. You never know there might be two versions down the line or another model that sits between the AZ100 and the AZ75.

I'm like the look AZ75 and can see one in my future. 

Edited October 19, 2021 by StarryEyed

[Stu]

Please, let’s end this nonsense now and concentrate on what is important. The decision has been made not to include slow motion controls because doing so would effectively just replicate a mount very similar in size, weight and cost to the current AZ100.

Rowan chose to differentiate the mount by making it much smaller and lighter, creating a much more manageable proposition for grab and go and travel use, easier to get to a dark site and easier to use for quicker sessions.

It is very smooth, and easy to use for planetary, lunar and solar tracking. I have put up with and enjoyed far worse in terms of stiction in the past, so it is a major step forward. Having encoders makes it a wonderful proposition for deep sky observing too.

This  mount will NOT have slow motion controls. It will likely have some tweaks to the design which will improve its useability. What Rowan choose to do in the future is up to them, I’m sure they will listen to the feedback but please, for the sake of my sanity, not another word on slow motions. The message has been conveyed and recieved, so any further repeats are pointless. And don’t say that you are being told what to think, you are not. The only thing anyone is being told is what is possible or not possible with this mount.

Now, back to a sensible thread about the testing of the AZ75 which will continue once the weather improves.

I have fitted one dual format saddle to the AZ75 from my AZ100 so that I’m ready to test my 130mm f6 on it at the next opportunity. I will remove the pillar so I can judge if it’s needed and give some input on how high it should be.

I also have a bracket coming to mount my Nexus on it to try out the encoders. I’m looking forward to that, having had a quick session with my AZ100 the other night to test it out. It worked really well, great for DSO and double star observing. I’ll try to add some videos on setting it up, and also on how the mount works with the heavier scope on board.

[Stu]

One further thought. I would think most people would likely use the mount on a Uni-28 or similar grade tripod, rather than a Planet. Does that sound sensible? I’m just thinking in terms of comparative tests I can mount both AZ100 and 75 on the Uni-28 and try to make some objective assessment about stability between them. Thoughts welcomed.

[dweller25]

@Stu Does the AZ100 have the multibase location nuts like the AZ75 ?

I have a UNI28 but with a Vixen GP/EQ5 fitting.

If not it would be a great if it could be changed…….

Edited October 19, 2021 by dweller25

[JeremyS]

5 minutes ago, Stu said:

One further thought. I would think most people would likely use the mount on a Uni-28 or similar grade tripod, rather than a Planet. Does that sound sensible? I’m just thinking in terms of comparative tests I can mount both AZ100 and 75 on the Uni-28 and try to make some objective assessment about stability between them. Thoughts welcomed.

Yes, if I got an AZ75 it would be to use on my Uni 28, likely with my Tak FC 100DZ. So would welcome your experiences, Stu.

I suspect it might be a bit big for my Report 312, but I would be interested in comparing AZ75 + Report  vs ScopeTech Zero + Report with Tak FOA 60Q

[Stu]

3 minutes ago, dweller25 said:

@Stu Does the AZ100 have the multibase location nuts like the AZ75 ?

If not it would be a great if it could be changed…….

From memory no it doesn’t, it has the EQ6 style base with one central M12 hole. I would go and check but it’s raining…… 🤣. The flat base does make a lot of sense and saves a lot of messing about. I tried the AZ75 on a home made adaptor for a Vixen GP and found a set of holes which worked pretty well to keep it centralised. Certainly something that I think they could look in to.

[Stu]

16 minutes ago, JeremyS said:

Yes, if I got an AZ75 it would be to use on my Uni 28, likely with my Tak FC 100DZ. So would welcome your experiences, Stu.

I suspect it might be a bit big for my Report 312, but I would be interested in comparing AZ75 + Report  vs ScopeTech Zero + Report with Tak FOA 60Q

Thanks Jeremy. I have a Planet, Uni-28 and a Gitzo GT5542LS which I can try it on. The Gitzo may give some idea of what it’s like on the Report. It is pretty sturdy but not up to Uni standards. I tried the mount on it to see if it would fit but haven’t put a scope on it in that configuration yet.

[Deadlake]

18 minutes ago, Stu said:

One further thought. I would think most people would likely use the mount on a Uni-28 or similar grade tripod, rather than a Planet. Does that sound sensible? I’m just thinking in terms of comparative tests I can mount both AZ100 and 75 on the Uni-28 and try to make some objective assessment about stability between them. Thoughts welcomed.

I think it would be very good to compare with different tripods, since I suspect A75 capacity is correlated to tripod stability.

[Stu]

3 minutes ago, Deadlake said:

I think it would be very good to compare with different tripods, since I suspect A75 capacity is correlated to tripod stability.

Absolutely, the tripod makes a huge difference. Even my little Giro-WR mount will take a big load when put on an EQ6 tripod. The Gitzo/AZ75 will make for a nice lightweight package but I wouldn’t put the LZOS on it, certainly not without a counterweight.

[Stephenstargazer]

22 hours ago, dweller25 said:

Does the AZ100 have the multibase location nuts like the AZ75 ?

No the AZ100 does not. But Rowan make an AZ100 M10 Pier Puck / EQ5 Tripod Adaptor for that mount which fits directly onto a Vixen GP/ EQ5 tripod head, and it does! I wonder if that would also fit the AZ75 base?

@Stu Whilst on the base subject is the center thread on the AZ75 base M10 or M12 ? (sorry if you have told us before!)

[Stu]

38 minutes ago, Stephenstargazer said:

@Stu Whilst on the base subject is the center thread on the AZ75 base M10 or M12 ? (sorry if you have told us before!)

Hi Stephen, it’s M10 and also fits 3/8” photo tripods which is handy.

[Stu]

Skies are clear here at the moment, so I removed the pillar, refitted the AZ75 to the Uni-28 and put my LZOS 130 f6 on, as well as my lovely Celestron Omni 120mm XLT (f8.3) to see how it fares with a longer scope. The XLT is a bit longer and about the same weight as a 120ED I think, so it’s a good test for that class of scope.

I tried out pointing at the zenith. The 120mm unsurprising definitely needs a pillar, the focuser wheel hit the tripod. With the f6, it is almost useable. In certain positions the diagonal hit the tripod but you could possibly observe with careful positioning. Actually the Rowan handle also hit the tripod but bear in mind I’m using the one designed for the AZ100. If not observing at the zenith then a pillar is not needed

My conclusion is that in current configuration a pillar of some sort is needed for observing at the zenith. It wouldn’t necessarily need to be that tall, perhaps 3 or 4” for the LZOS type scopes and higher for something like the XLT.

I tried some very high powers out too, Vixen 3.4mm HR in a Zeiss Abbé Barlow giving x458. Venus was showing early on so I tried that. The view wasn’t great, lots of atmospheric CA but that wasn’t the point. It was quite easily trackable with good balance and the tension set just right. The mount seemed stable, with well damped vibrations so these two seem to go well together. I’m sure the Planet would improve things but that becomes a bigger, heavier setup so misses the point of the lighter mount I feel.

I also experimented with just the LZOS on either with no counterweight, and also with the counterweight in two positions, the middle of the bar and at the end. Honestly I couldn’t really tell much difference in smoothness, they all seemed fine. I tried my infamous spin test and with the counterweight half way out on a full length bar, I thought it was never going to stop; it went for nearly 2 minutes! I have yet to perfect a standard ‘Stu push’ though so it’s quite unscientific. So, my conclusion on that score is that counterweighting a heavy scope seems to have some effect but actually the difference in feel when at the eyepiece was essentially unnoticeable. It’s more about overall stability of the system ie avoiding the tripod toppling over than improving the motion of the mount.

[Deadlake]

41 minutes ago, Stu said:

Skies are clear here at the moment, so I removed the pillar, refitted the AZ75 to the Uni-28 and put my LZOS 130 f6 on, as well as my lovely Celestron Omni 120mm XLT (f8.3) to see how it fares with a longer scope. The XLT is a bit longer and about the same weight as a 120ED I think, so it’s a good test for that class of scope.

I tried out pointing at the zenith. The 120mm unsurprising definitely needs a pillar, the focuser wheel hit the tripod. With the f6, it is almost useable. In certain positions the diagonal hit the tripod but you could possibly observe with careful positioning. Actually the Rowan handle also hit the tripod but bear in mind I’m using the one designed for the AZ100. If not observing at the zenith then a pillar is not needed

My conclusion is that in current configuration a pillar of some sort is needed for observing at the zenith. It wouldn’t necessarily need to be that tall, perhaps 3 or 4” for the LZOS type scopes and higher for something like the XLT.

I tried some very high powers out too, Vixen 3.4mm HR in a Zeiss Abbé Barlow giving x458. Venus was showing early on so I tried that. The view wasn’t great, lots of atmospheric CA but that wasn’t the point. It was quite easily trackable with good balance and the tension set just right. The mount seemed stable, with well damped vibrations so these two seem to go well together. I’m sure the Planet would improve things but that becomes a bigger, heavier setup so misses the point of the lighter mount I feel.

I also experimented with just the LZOS on either with no counterweight, and also with the counterweight in two positions, the middle of the bar and at the end. Honestly I couldn’t really tell much difference in smoothness, they all seemed fine. I tried my infamous spin test and with the counterweight half way out on a full length bar, I thought it was never going to stop; it went for nearly 2 minutes! I have yet to perfect a standard ‘Stu push’ though so it’s quite unscientific. So, my conclusion on that score is that counterweighting a heavy scope seems to have some effect but actually the difference in feel when at the eyepiece was essentially unnoticeable. It’s more about overall stability of the system ie avoiding the tripod toppling over than improving the motion of the mount.

If you has a counterweight on the LZOS scope could you move the scope forward and clear the tripod? I’ll take some pictures of mine tonight.

[Stu]

52 minutes ago, Deadlake said:

If you has a counterweight on the LZOS scope could you move the scope forward and clear the tripod? I’ll take some pictures of mine tonight.

Yes, most likely. Trouble is I have a very short Losmandy plate on it so nowhere to attach anything really. I do have a longer one but need some standoffs to avoid it hitting the dewshield.

[Stu]

1 hour ago, Deadlake said:

If you has a counterweight on the LZOS scope could you move the scope forward and clear the tripod? I’ll take some pictures of mine tonight.

Actually, someone should make a lead finder and holder, that would help 🤪🤣

[Deadlake]

3 minutes ago, Stu said:

Actually, someone should make a lead finder and holder, that would help

I was going to say it's called a FT focuser, but even this neutron star material cannot balance the black hole of the LZOS triplet.  😀

[Stu]

I’ve packed in now as am feeling lousy. Just wanted to try those bits out, wasn’t planning on a long session which is just as well. It may be clear, but the transparency is poor, as is the seeing! I was hoping for better things after the rain.

I did setup the Nexus and got it connected with now problem. Trouble was I didn’t know the number of ticks for the encoders. Guessed at 100k, then 125k and finally 126k but the accuracy was off. I read Alan’s reply too late; 128k is the answer. Corrected now in SkySafari so it should work first time next time.

The little plate fits fine onto the mount, and two straps hold the Nexus in place. Simple but it works.

So, have found out a few interesting bits and pieces today. Next time will try it on the Gitzo to see how stable it is on that.

[Stu]

11 minutes ago, Deadlake said:

I was going to say it's called a FT focuser, but even this neutron star material cannot balance the black hole of the LZOS triplet.  😀

Wonder how much heavier it is than the standard one. That’s pretty substantial already.

[johninderby]

You could always use a Lumicon Superfinder. I don’t use it on most scopes as it makes them too back heavy. 3mm wall thickness tube  and long drawtube is a bit heavy..Still it means it can be used as a right angle or straight through finder.

Edited October 21, 2021 by johninderby

[Deadlake]

Went out tonight, meant to be very clear however cloud's rolled in and seeing and transparency poor. Glad to be out and given the quick setup/tear down time not a wasted night.

On clearance:

 

It's the pan handle which is really causing the snagging. Note this pan handle that is 4" shorter than the stock model, a Derek special.

The focuser can always be moved and to be honest I never need it out that far. 

Options:

1) Replace Avalon EQ6 bolt with the Baader EQ6 equivalent which has a base that add's a couple of cm's.
2) Buy a Rowan saddle so the pan handle can go the other side. I would buy one anyway to mount two scopes with Losmandy rails. Any other location I can mount the pan handle? Maybe if bracket attaching the pan handle to the saddle could be at an angle, then the snagging would never happen @RowanAstronomy? Same issue @Stu in previous post.
3) Get a half pier, which I might have to do in the future. A 55 mm Tele Vue Possl needs a feather touch extension tube to come into focus, in this case the pier is only solution. 

Other side:

 

[Stephenstargazer]

20 hours ago, Deadlake said:

Any other location I can mount the pan handle?

https://stargazerslounge.com/topic/384795-rowan-az75-mount/?do=findComment&comment=4157075

Was my answer to similar comment on the other thread. Wont suit all but works for me 🙂

[Deadlake]

30 minutes ago, Stephenstargazer said:

https://stargazerslounge.com/topic/384795-rowan-az75-mount/?do=findComment&comment=4157075

Was my answer to similar comment on the other thread. Wont suit all but works for me 🙂

I think this is a common occurrence, I'm sure Derek will come up with a way around this. 😉