First Play with DSS, but no stars in M13

[SnakeyJ]

Just having a little play with the QHY5L-II, prior to modding - but wanted to have a quick attempt at M13 last night. I was actually quite pleased with the quality of the resulting frames and took 100 x 3sec light frames (red channel only) and 10 x darks. All frames saved as TIFF from source AVI using PIPP. However, no matter what star detection threshold settings I put in to DSS it finds no stars in any of the subs. My reference frame is below:

Whilst this is certainly nothing special, I'm sure I have more stars than hot pixels!

I've had a quick look through a couple of tutorials and googled no star detection in dss (only hits seem to relate to EOS FITS frames).

Have I done something fundamentally wrong on the capture or am I missing something obvious in DSS?

[Jgw]

Hi Jake,

Don,t worry mate, this is the normal procedure, we all have gone throuh this!! :icon_scratch:

Any chance of loading up your sub files, Then i can have a better look.?

Cu john

[SnakeyJ]

Don,t worry mate, this is the normal procedure, we all have gone throuh this!! :icon_scratch:

Any chance of loading up your sub files, Then i can have a better look.?

John - I don't think that SGL allows me to post TIFF files to my Gallery, so I will zip up 25 of the subs and upload to dropbox - a couple of minutes!

[SnakeyJ]

Okay, I have 25 handpicked frames from the first 45 - which have zipped down to 10Mb, which should be available here - https://www.dropbox.com/s/5dahvmu8keo9oat/M13.zip

Not expecting too much from this data for a first attempt, but it would be nice to know what I've done wrong and if I can salvage and stack for practice/familiarities sake.

Thanks for looking - Jake

[Adamar98]

The image is very noisey. I think DSS will struggle to tell what are stars and what is noise. I'm fairly new to imaging so I could be wrong.

[Leveye]

When i click the image above i get a grey background with almost all white pixels just to about the center and some image in the very center don't see how DSS could process that correctly.

[cgarry]

The image fails to display in the browser for me, but it is fine if I save it and open it with a normal image viewer.

[SnakeyJ]

Cheers everyone - I have managed to get DSS to play on this, though I had to go back to some data without automatic dark frame subtraction, be very picky with the frames to stack and play around for ages with the detection settings until I got a result. The data certainly was very noisy, and star shape was certainly not helped by the wind vibrating my mount around during 5 second exposures (on packing up I realised that I hadn't re tightened the leg brace after polar alignment).

No work or art I'm afraid, but it definitely is M13 and my first ever DSO image - now whats the correct orientation

I will definitely have another go at this with LRGB prior to modding the camera, if nothing else it demonstrates how noisy an uncooled cmos can be....

[Leveye]

Nice work!

[SnakeyJ]

The image fails to display in the browser for me, but it is fine if I save it and open it with a normal image viewer.

Thanks Chris - my copies weren't doping that before uploading, possibly to do with browser display or scaling? The finalised version seems to behave ok though.

To be honest I'm chuffed just to get something out from what was just a 20 minute play/experiment after imaging Saturn last night. Even if the sensor is very noisy at these gain settings, it certainly is sensitive enough for its primary purpose as a guide cam.

[SnakeyJ]

Nice work!

Thanks Leveye - not quite sure what's happening with the OP image, the version uploaded to the Gallery displays ok. Very pleased to get something out after banging my head against the wall all day, but as a complete novice to DSO imaging its the intro to DSS rather than the final image that's most important.

[Jgw]

Hi Jake, so just home from work.. as you have noticed, you have managed on you own...

That is a good start, be happy with that....

Cu John

[Adamar98]

That's a much better image!

[SnakeyJ]

Hi Jake, so just home from work.. as you have noticed, you have managed on you own...

That is a good start, be happy with that....

Cu John

John - thanks for the offer it was much appreciated - fortunately I had little urgent going on at work at day and spent the best part playing with DSS and some Saturn capture from last night. Being very selective on quality and mitigating the noise seem to be the two most important factors. Though very impressed I managed to get that much out of a first quick play, another great piece of software that I need to learn my way around .

That's a much better image!

Adammar - thanks also, very relieved to get something to show for a whole day spent sitting on my ar*e

[tonedeaf]

..... if nothing else it demonstrates how noisy an uncooled cmos can be....

cutted quote....

oh yes!

still wondering about the canon dslr´s how they manage the noise "uncooled"

oh back to topic!

i like the image.