ZWO ASI 2600MM-PRO or QHY268M

[teoria_del_big_bang]

There seems to be a lot of talk about these two new mono cameras.
I just wondered which camera people have chosen and maybe a post to say why.
The QHY is quite a bit cheaper, the ZWO is a little lighter but apart from that cannot see much to choose between them.
The poll is really only for those who are serious about getting one of these and have looked into buying both (i.e. not just gone for ZWO because they always use ZWO etc).

A post also to say why you made that decision (i.e. ordered to take advantage f introductory offer, or will get one but waiting to see if any issues and so on).

[Dinglem]

I like many are probably waiting to see what the early adopters think of these new cameras once they have them and used them a while. I would like to buy either as I would like to get into mono imaging, but at this price point I want to be sure I'm getting as good a product as is being promised by each manufacturer.

[tooth_dr]

I have a QHY268M ordered, should be here next week.  The decision was influenced by availability and by cost, and by reputation of both vendor (MA) and QHY.  I already own QHY cameras so I trust the brand.  If the ZWO had been available when I ordered the QHY and was the same price as the QHY then I may would have chosen the ZWO.  However I dont like to invest too much in one brand, and prefer to have a variety of cameras, scopes etc.  I recently bought a ZWO2600MC, and was specifically after a matching mono camera for a dual rig.

 

Edited January 27, 2021 by tooth_dr

[teoria_del_big_bang]

11 minutes ago, tooth_dr said:

If the ZWO had been available when I ordered the QHY and was the same price as the QHY then I may would have chosen the ZWO.  

I am very much the same, not yet ordered but hovering over the buttons.
I have had no issues at all with my ZWO ASI1600MM, but there again mine is only a couple of years old so not an earlybird and I guess any issues will be the early buyers. So very much wanted a 2600 and would pay the extra £300.

Any particular specification reason you would have bought the ZWO all other things being equal ?

Only issues I have is I want to buy a new FW to go with it as using my SX will add to the spacing between the 36mm filters and image plane, also worried about the extra weight on the fairly flimsy outside cover of the SX, and I am liking the QHY wheel over the ZWO and I would think best to get both camera and wheel from same company.

And when it comes down to it I cannot see any advantage of the ZWO over the QHY apart from the USB2 hub and the weight reduction (the latter probably more use.
So I am really edging towards the QHY.

I would love to see some pics of the dual rig and some of the images 🙂 

Steve

Edited January 27, 2021 by teoria_del_big_bang

[Dinglem]

Also doesn't the QHY have 4 times more buffer memory?

[teoria_del_big_bang]

4 minutes ago, Dinglem said:

Also doesn't the QHY have 4 times more buffer memory?

I think that's correct and it is how I read it. I was more looking at advantages the ZWO had and why I should pay £300 more and wait longer but yes should also be looking at advantages of the QHY.

Edited January 27, 2021 by teoria_del_big_bang

[JamesF]

9 minutes ago, Dinglem said:

Also doesn't the QHY have 4 times more buffer memory?

I have wondered in the past whether that's because having four times more memory is useful, or if there's negligible cost difference between the two and having the larger amount is just another bragging point.

If each frame is about 50MB, what are you going to be doing that requires 2GB of buffer to store the data during transmission to the host system?  50MB doesn't take a huge amount of time to transfer over a USB3 link (less than half a second?), especially compared to the lengths of exposure used in deep sky imaging, and if your frame rate is so fast that you're creating a backlog of frames to be transmitted on the camera then a 2GB buffer is hardly buying you lots of breathing space.

James

[teoria_del_big_bang]

25 minutes ago, JamesF said:

I have wondered in the past whether that's because having four times more memory is useful, or if there's negligible cost difference between the two and having the larger amount is just another bragging point.
If each frame is about 50MB, what are you going to be doing that requires 2GB of buffer to store the data during transmission to the host system?  50MB doesn't take a huge amount of time to transfer over a USB3 link (less than half a second?), especially compared to the lengths of exposure used in deep sky imaging, and if your frame rate is so fast that you're creating a backlog of frames to be transmitted on the camera then a 2GB buffer is hardly buying you lots of breathing space.

Some of this is a bit over my head but I think these cameras each frame is about 120Mb, however, still for normal exposure times still doesn't really require that memory so I guess only an advantage to taking lots of short frames such as planetary imaging, but I am thinking the main buyers of these cameras will be using far longer exposure times.

[Dinglem]

@JamesFsorry my point was not very well put on reflection, I agree with what you have said there is no benefit to performance in having the extra memory due to the size of each frame. It was stated that why is the ZWO £300 more expensive for what is basically the same camera, same chip etc. and I was saying it also had a larger buffer, that will in effect cost more even though memory costs are certainly a lot cheaper these days than when I started buying it.

Edited January 27, 2021 by Dinglem
too many wills

[JamesF]

6 minutes ago, teoria_del_big_bang said:

Some of this is a bit over my head but I think these cameras each frame is about 120Mb,

Possibly when a frame is saved as RGB from the colour version of the camera?  With 26 megapixels and a sixteen bit (two byte) ADC, the actual amount of data coming off the sensor can't be more than 52MB though, can it?

James

[teoria_del_big_bang]

14 minutes ago, JamesF said:

Possibly when a frame is saved as RGB from the colour version of the camera?  With 26 megapixels and a sixteen bit (two byte) ADC, the actual amount of data coming off the sensor can't be more than 52MB though, can it?

Ah yes I think it was a review on the colour version I read that. I think I just thought that mono would be the same having same number of pixels but I think you are right and we generally agree for DSO use the extra memory is not really an advantage.

Steve

[DaveS]

I went with the QHY due to the reputation of the company, have a look on their site, some serious professional cameras on there, and looking at the 268 the build quality, and the fact that it has multiple readout modes.

I also have great respect for Rupert at Astrograph, who has repeatedly gone above and beyond.

[tooth_dr]

31 minutes ago, teoria_del_big_bang said:

Ah yes I think it was a review on the colour version I read that. I think I just thought that mono would be the same having same number of pixels but I think you are right and we generally agree for DSO use the extra memory is not really an advantage.

Steve

The colour is around 50mb too.   My 36mp DSLR raw files are 77mb. 

Edited January 27, 2021 by tooth_dr

[Starflyer]

I've been hovering over the buy button on the QHY but I think I'll hold off until the summer.

For me it'll mean a new filterwheel, filters and OAG, so the early bird discount isn't as important as getting it right first time.

I may well end up buying ZWO, by holding off for a while I get the benefit of seeing what problems each brand's camera has after launch, if any.

I haven't owned a serious camera from either brand, but my gut feel is saying go with QHY. If Atik launched a camera with the same sensor then that's where my money would go.  This hobby is difficult enough at the best of times and reliability means everything to me.

[smr]

5 hours ago, tooth_dr said:

I have a QHY268M ordered, should be here next week.  The decision was influenced by availability and by cost, and by reputation of both vendor (MA) and QHY.  I already own QHY cameras so I trust the brand.  If the ZWO had been available when I ordered the QHY and was the same price as the QHY then I may would have chosen the ZWO.  However I dont like to invest too much in one brand, and prefer to have a variety of cameras, scopes etc.  I recently bought a ZWO2600MC, and was specifically after a matching mono camera for a dual rig.

 

Is that to combine luminance from the mono with rgb from the osc or will you be using an efw and filters with the mono?

Just asking as this is something I've been thinking about, it'd be great to have two scopes the same and a mono and osc camera of this sensor.

[smr]

12 minutes ago, Starflyer said:

I've been hovering over the buy button on the QHY but I think I'll hold off until the summer.

For me it'll mean a new filterwheel, filters and OAG, so the early bird discount isn't as important as getting it right first time.

I may well end up buying ZWO, by holding off for a while I get the benefit of seeing what problems each brand's camera has after launch, if any.

I haven't owned a serious camera from either brand, but my gut feel is saying go with QHY. If Atik launched a camera with the same sensor then that's where my money would go.  This hobby is difficult enough at the best of times and reliability means everything to me.

That's fair enough and quite sensible. Although saying that, I don't think there will be much to choose between both Cameras if they are anything like their OSC models, I'm not sure how the design and manufacturing differs between Mono and OSC though so we'll have to see what they're like when people really begin to start imaging with them. 

[tooth_dr]

8 minutes ago, smr said:

Is that to combine luminance from the mono with rgb from the osc or will you be using an efw and filters with the mono?

Just asking as this is something I've been thinking about, it'd be great to have two scopes the same and a mono and osc camera of this sensor.

I started off doing it with a mono and a DSLR, but the colour was noisy.  I ended up then going to two mono, used one for colour with filters and one for lum, or one for Oiii and one for Ha.  This time, I'm hoping the OSC will make it easier to get that colour data, and even with a dual filter, it will still perform ok for NB.

[Spongey]

I have ordered the QHY 268M for similar reasons to those mentioned above, but primarily availability and price. 

If the two cameras were the same price then I probably would have gone with the ZWO, but £400 is a significant chunk. If I end up needing a USB hub then I'm sure the savings from the camera will cover it 

Considering both of these cameras are based on their colour counterparts, one other thing possibly worth noting is the issues with residue on the 2600MC sensor due to grease used in manufacture. I haven't heard of any similar issues with the 268C.

Edited January 28, 2021 by Spongey

[Xiga]

My next camera will definitely be an IMX571 one, but i haven't yet decided on whether it should be Mono or OSC. At the moment, I'm leaning towards Mono and pairing it with the D5300 for colour. 

Weight is an issue for me though. My wee 80ED's stock focuser is currently just about managing the Atik383l+ (at 750 grams). The ZWO weighs a similar amount, but the Qhy weighs just over 1Kg! which is just too heavy for me i think.Quite annoying really, as the Qhy is available now and at a very good price. In all likelihood, i'll probably just hold off until Autumn and see how things are looking then. 

[tooth_dr]

6 minutes ago, Xiga said:

My next camera will definitely be an IMX571 one, but i haven't yet decided on whether it should be Mono or OSC. At the moment, I'm leaning towards Mono and pairing it with the D5300 for colour. 

Weight is an issue for me though. My wee 80ED's stock focuser is currently just about managing the Atik383l+ (at 750 grams). The ZWO weighs a similar amount, but the Qhy weighs just over 1Kg! which is just too heavy for me i think.Quite annoying really, as the Qhy is available now and at a very good price. In all likelihood, i'll probably just hold off until Autumn and see how things are looking then. 

I had 1.8kg on the focuser on my ED80, and I didnt really find any issues mechanically.  I never really scrutinised the star shapes, but felt they were ok also.  Perhaps your focuser could be tweaked a little?

[Xiga]

34 minutes ago, tooth_dr said:

I had 1.8kg on the focuser on my ED80, and I didnt really find any issues mechanically.  I never really scrutinised the star shapes, but felt they were ok also.  Perhaps your focuser could be tweaked a little?

Wow, 1.8Kg! I've adjusted mine a couple of times over the years, to try and tighten it up. Each time, i had to go and find the webpage to remind me of which screws to adjust, but tbh, it always felt like trial and error to me, even though i did see a small improvement. It sounds like i need to have another go and see if it can be improved further.

I just use the basic SW handheld auto-focuser. Hopefully it's up to the job too. What were you using to focus when you had that amount hanging off yours Adam? 

[tooth_dr]

4 minutes ago, Xiga said:

Wow, 1.8Kg! I've adjusted mine a couple of times over the years, to try and tighten it up. Each time, i had to go and find the webpage to remind me of which screws to adjust, but tbh, it always felt like trial and error to me, even though i did see a small improvement. It sounds like i need to have another go and see if it can be improved further.

I just use the basic SW handheld auto-focuser. Hopefully it's up to the job too. What were you using to focus when you had that amount hanging off yours Adam? 

Dont want to derail the thread, but yes I just used the same handheld SW motor that takes the 9v battery. I did find that the motor coupling could slip on the shaft, due to the way it relies on a friction grip with a rubber O ring.  I added a grub screw to that, and it was solid.  In fact I had two ED80s, with same kit, so Im pretty sure it wasnt a fluke.

[teoria_del_big_bang]

QHY 268M ordered together with a QHY filter wheel 7 x 36mm (basically a freebie with the introductory offer ).

I am sure it is not but somehow choosing which camera to get seemed like the hardest decision I ever made.

Steve

[Xiga]

I'm pretty much sold on the Qhy 268M now myself. 

However, i was doing a little searching online, and i came across this review of the early bird version of the OSC one. 

https://www.astrophotoygk.com/post/qhy268c-camera-review-best-astrophotography-camera

Look at the length of that monstrosity, it's 180mm long! I really don't like the thought of such a long camera hanging off the back of my scopes. Qhy's website has a drawing that states it is actually only 102.8mm, but then it says that's for the Photographic version, which hasn't been released yet (and which apparently will weight 780 grams). I've emailed Bern to see if he knows for sure how long this early bird version will really be. 

[teoria_del_big_bang]

Yes that nearly threw me off it as well but I am pretty sure that was just the earlybird version.

This is the drawing that is on the websites selling the current model is a maximum of 110.8 mm.
Strangely it shows the same drawing on some sites for colour and mono but the mono version, as far as I am aware) does not have that 10 mm dovetail for the rotator but not sure if that means it is 102.8 mm or it has something else that replaces that dovetail that will also be 10 mm long.

All the videos on youtube I have seen about the colour version they certainly weren't 180mm long.

If anyone finds a proper drawing of the Mono version please post it on this thread 🙂 

The slightly shorter length and reduced weight was what really made me want the ZWO version but so long as that drawing is correct then the extra length is only about 14mm, so I can live with that and the weight, well we will see 🙂 

Steve