Tommohawk

I guess so but you'd think a "casual" photographer would just stick to AVI.

There's lots of threads out there about folks struggling to achieve download speeds and struggling with monster file sizes, so I can't see why Torsten has opted for debayered with Firecapture... it seems odd, especially given what you say about AS!3 preferring undebayered.

Ok I need some time to digest that! But if working with undebayered data is best why does fire capture used debayered capture?

Hi Vlaiv and thanks for that the maths seems to fit with my situation. 

Today I fired it up again just to recheck before tidying everything away and it all went wonky for some reason and froze... not sure why. Anyhow, I did some further tests and the maths you  outline stacks up very nicely.

With Toupsky I  can select RGB24 or RAW, and separately I can select 8bit or 12bit, and also AVI or SER. All combinations seem to be allowed. Most folk agree that when doing many frames 8 bit is fine, so that would suggest RGB24, SER 8bit... correct?

Previously I've used AVI just because the files open with a wider range of software, and also because with Toupsky for some reason the Timestamp which gives the FPS isnt recognised in PIPP or in Windows metadata. Maybe an issue with Toupsky. But I can live without that because the FPS is easy to calculate.

Also I didn't notice the file size difference with SER and AVI in Firecapture and have just rechecked that - AVI and SER files are same size. I can also see that Firecapture seems to capture debayered - it reports it in PIPP as mono.

So after all that, my question is.... if undebayered SER files are smaller than mono SER and smaller than AVI, why doesn't everyone work with undebayered SER?

Smaller files and presumably faster capture speeds, no?

Short version is I'm struggling to get claimed frame rates with my OmeGON Velox 385 at full res. It seems OK when I restrict ROI, which for me is normal when doing planets, but when doing lunar I like to use entire full res frame.

The only capture software which seems to work with Omegon is Toupsky - and to be fair its really good. Today I updated to a new version and the frame rate seemed much improved - reaching around 130 as claimed. However, it still doesnt download at that rate.. only about 35 fps. There no RAM allocation of buffer as in Firecapture BTW.

Trying a few different things, I discovered that if I used SER format, I got much better rates - the full 130 fps. For some reason the timestamp/FPS isnt recognised by PIPP, but simple maths shows the number of frames is correct for 130 FPS.

However... I notice the SER frame size is rather smaller that the AVI file. Is that correct? Maybe its because its not debayered? Now if that were true, it would be an obvious reason for using SER in preference to AVI - much smaller file sizes. But I've read all I can on this and nobody seem to mention that SER files are smaller than AVIs.

So am I missing something??? Grateful for any help!

11 minutes ago, teoria_del_big_bang said:

I tell a lie I have found 1, but it really is an odd cold pixel that is all.

Good spot! TBH if there's only 1 dead that's probably pretty good. 

Hi Steve - thanks for checking. 

I'm sure its all OK ... what got me started was just checking that I had done the darks with the same offset (64) which Ive adopted for lights and flats. And when I saw that "minimum ADU value" as 16, I thought that cant be right. But as you say no pixels are that low. So not sure what that represents! Anyhow the darks seem to work OK, so hopefully all good.

Some of this stuff is still a bit of a mystery to me ....!

Thanks Steve, thats good of you.  - see attachment. Yes, individual frames not master.

 2020-03-28_23-26-49_SII_-20.00_60.00s_139.00_64.00_64_.fits

Hi and thanks for your reply. ASI1600 cool.

But I think I may be misunderstanding the FITS data. The image below suggests "Input minimum 16" But when I hover over pixels the lowest value is about 592....  so I think its OK and I'm just mis-reading the data.

Does that make sense?

Just been reviewing my darks and notice that the minimum ADU (shows in FITs liberator) is 16, with offset set at 64. How is that possible?? Maybe I'm misunderstanding the units or something.

Grateful for any thoughts!

34 minutes ago, mikemabel said:

The mount is a HEQ5 pro belt modded from FLO my most expensive purchase being disillusioned with the time actually using my kit Vs expense I sold a lot of items and decided to concentrate on the basics and limit my expense though I've got the enthusiasm back so I may take the plunge ie new camera and scope in the future . I've got dithering working well with guiding so I don't need darks...or do I ??

As you say I need more subs but I've been reall pleased with my earlier attempts

Clear skies

Yeah I have HEQ5 with belt mod too works great... usually! Yours certainly looks good.

Darks - conventional wisdom was that you want darks especially with DSLR, temperature matched as near as you can. But... there are other views out there on darks! I used them religiously but some folk say they introduce noise, and dithering helps even out the noise so that darks not required. 

I also think you might want to look at your flats, which you definitely do want  -they don't look right. 

Hi All. I thought this target was stretching things a bit for my kit and FL - it's 45 million light years away after all!

But to really screw it up I forgot to put the heater on the secondary! I connected it OK, but forgot to switch on the battery!

I didn't realise until I switched to the last (red filter) which needs a tiny refocus - initially I though it was just some dew on the screen, but no.... the images are horrible and the secondary was totally dewed up. Hey-ho.

So the data absolutely sucks - but I processed it just to see if it would be doable under normal conditions and I think the answer is yes. In fact TBH the end result is surprisingly good. Sky not looking good for the immediate future though so fingers crossed!

HEQ5, SW200P, ASI1600 @-20, 71x60s LUM and 40-80 x 60s RGB. (RGB Unbinned to try and keep detail in small target) APP and PS. I used SW CC which is x0.9 only to make connection easier/firmer. Optically probably would have been better without it. Cropped the final image.

Thanks for looking!

That's really nice Göran - and yet another target I'm unfamiliar with!

But I don't think I'll be putting it on my list.... it looks too challenging for my site and kit... .and abilities!

Yes thats a good start for such limited exposure. More subs would be the main thing. Also just wondering what mount youre using and if youre guiding - whatever youre doing the stars look quite nice so maybe you could do longer subs? Aaaah - just noticed you said guided. So maybe extend subs, or if not possible consider more subs and use ISO1600

Also to be picky your flats dont seem quite right - some vignetting, no?

Nice work with  modest kit! Looking back I think I got more enjoyment out of my early AP with  basic kit than I ever have since with more expensive kit, so make the most of it!

That spacer setup is exactly what I have and it works fine for me - so your image seems odd. The filter type / thickness might make some difference, but not a lot. As Clarkey said, maybe some more info on what CC and scope you have would help. 

12 hours ago, Clarkey said:

Great image 👍. The multi star guiding definitely helps in my opinion.

Thanks. Re multi star guiding wonder if it also makes it easier to pick up guiding after any passing clouds? Although guiding was good there was one brief period where star was lost, but seemed to resume OK.

12 hours ago, Catanonia said:

Nice, I am trying this tonight with the RASA 8, if only the clouds would stay away

Thanks. RASA 8 - that's the tool for the job! Look forward to seeing your results.

Hi all.

I saw a couple of lovely renditions of this online somewhere and thought I'd give it a go. Switching from my PDS200 with CC to the widefield refractor is easy now as they both use 55mm backfocus. That said I noticed the spacing was about 1mm out so removed a thin (0.25mm) plastic spacer from between the camera and the EFW - forgetting that my very dodgy flats would then be even more dodgy!

Actually this turned out to be a blessing in disguise, because my NB flats have always been a problem - and it turns out this may be to do with the non-linear nature of the camera. I re-did the flats using the NINA flats wizard and set the mean ADU much lower - about the same as the mean ADU of the lights. And finally after 4 years of banging my head against a wall I finally have NB flats that don't overcorrect vignetting - hurrah!

OIII for this was stretched to blazes so lots of blue haloes - I've reduced the worst of them.  I didn't really like the periphery of this image either - we have LED streetlights now and pretty sure this causes very slight gradients which is enough to muck up faint data. So I did a cropped square which I think frames quite nicely.

Anyhow, about 3 hours per filter, and pretty pleased with the outcome - as ever more data would be nice! Guiding was amazingly good (for me anyhow!) at 0.49" RMS. I'm now using multi star align on PHD2 and maybe this makes some difference?

HEQ5, Sharpstar Mk1 61 EDPH, ZWO MkII NB filters, NINA, APP, PS. (300sec subs, -20C)

Thanks for looking - -grateful for any comments. 

Lovely image, nice detail - another new one on me too!

Gosh is it Pleiades time of year already?!

Lovely image and I agree for a bright blighter it can be tricky to process - I think you've done a great job, especially as only 3.5 hours. I might have pushed the blue a bit but maybe thats just me.

Nice job!

Right - been away for a week, back now..... and Neil you were right - I hadn't checked RGB align in my new version of AS!3. Redid the image using similar processing steps in PS and definitely better.

👍

37 minutes ago, Captain Magenta said:

If you detach the mirror cell and the spider you could probably get both in? 😄

Yeah probably! It's finding time for both that's the real challenge though!

Re RGB align, yes done quite a bit of planetary now so familiar with that... But.. just updated to AS3 and maybe I didn't check RGB align. Thanks for the heads up!

Re bit depth, I've always captured in lower bit depth with ZWO firecapture but wasn't sure about Omegon Toupsky combo. Everyone seems to agree is ok so I'll try that. Thanks all. 

Lol. To be fair she is much better company than Newt.

Hi all.

Away with campervan at the moment, and tonight had lovely clear skies. Big moon too though, so no good for deep sky. Could have brought my big newt and done some planets... but brought my wife instead. No room for them both! 

So did a widefield pic instead with Jupiter and Saturn - hope you like it!

23 hours ago, AKB said:

Thanks for that.  A bit off topic, but how did you fix the focuser to the vanes?

Difficult to see from that pic and I'm away at the moment so cant post better one. I got an eyepiece adapter of some sort and drilled out the barrel to attach the vanes with M2 (I think) screws/nuts. That holder is then used to clamp the powermate and the camera is held in the powermate in normal way. It was a bit tricky cos I had to counterbore the barrel from the inside to accommodate the nuts. I ground a special tool - cant remember what I made it from now! The vanes are then tightened in the normal way, but pretty tight..... its surpisingly solid.

1 hour ago, CraigT82 said:

I love your scope! Top modding that is 👍👍👍

Nice Jupiter... The image is suffering from atmospheric dispersion so squeezing an ADC in there would give worthwhile benefit I think, if you could? 

As for the 8 bit captures, this is recommended as offers best frame rates and it's the stacking of thousands of frames that restores the lost bit depth (I'm some way that I don't really understand!)

Thanks Craig. As a mod I'm quite chuffed with it, especially as I dont have a fancy workshop. Mostly a question of adapting bits.

I'd like to repeat this scope design with say a 400mm mirror but it could prove to be an expensive mistake!

The ADC could be added in the path - I would just need to adjust the tube length by the length of the ADC. It would add more torsion force to the vanes though, and also the diameter is 46mm which would enlarge the CO which would defeat the object somewhat.

Re 8 bit - yes I gather that with the ZWO cameras at least the bit depth is restored in stacking. That bits a mystery to me too! I just wasnt sure if this would also be true with the OMegon

On 17/09/2021 at 22:59, si@nite said:

A reasonable shot there Tom, conditions have not been great of late anywhere in the uk it seems.

Regarding captures in 8 bit absolutely fine there should be no restriction or limitation in the information captured whatsoever, i usually shoot around 90fps with a 640 x 480 window as a rule!

8 hours ago, morimarty said:

Well done on your image Tom. Thats a very interesting set up you have a Fastar newtonian? I use firecapture and it as two options 8 bit or 16 bit  my asi290mm is 12 bit but I do capture in 8 bit and had no problems or noticed any detriment in quality.

Ok thanks for that. I capture in lower bit rate with Firecapture  when using my ASI290MM but not sure about how it works with  Omegon/toupsky combo, Given time I could just experiment but never get enough time/clear sky

6 hours ago, AKB said:

I’ve always wanted to try this, although for EAA rather than planetary.  You have a helical focuser?  How do you align?

Tony

Yes it would be good for EAA, though I haven't done this yet.

Here's a picture of the scope. The idea was to minimise the central obstruction to improve resolution, and also to devise a lightweight transportable strut or truss design for easier transport. I happened to have a 250mm Quattro which I was using much, and a 250 flextube tube only came up for sale, so I combined the two. Coarse focusing is done by adjusting the tube length using the tube extension clamps. Once done thats left alone and then just use the helical focuser to fine tune. I have to focus by Bahtinove which is a bit fiddly but not too bad. 

Target location is challenging. The finderscope is set quite precisely and I can usually get close enough to align the target roughly... it is a bit of fun though!

There is no discernible benefit in resolution but I think thats simply because this grade of F4 mirror is compromised optically. If I were repeating I would probably use an F5.