Clarkey

If you tape the white t-shirt (or some A4 white paper) between the flat panel and an acrylic sheet this makes a very even flat panel. This is what I use for up too 200mm scopes.

As said above it is probably light getting in. Unless is completely dark I put a lightproof cover the whole scope to do flats. The acrylic sheet arrangement will allow light in from the sides. I try to do my flats during set up now, that way if I have to cut a session short I already have the flats done in the dark.

13 hours ago, alacant said:

If you want to be certain, all the 18mp sensors we've tried are clean. 600d, 700d, 4000d etc

I have a 600D which does give some banding. I can just about remove it in processing but it is a pain. Most 600D's seem pretty good though - I think mine just has an attitude problem😂

I use one of these with a few sheets of paper under it.

AGPTEK Magnetic Tracing A4 LED Light Box Drawing Pad Dimmable Brightness, Physical Buttons Control, USB Power Cable for Animation, Designing, Stencilling X-ray Viewing/Sketching Diamond Painting : Amazon.co.uk: Home & Kitchen

For my smaller scopes I use a tablet with a 'white screen' app.

I got one of these to extend the life of my laptop:

https://www.amazon.co.uk/s?k=19v+laptop+portable+power+bank&crid=20JG5BAWVAMV2&sprefix=19v+lap%2Caps%2C185&ref=nb_sb_ss_ts-doa-p_3_7

Gives me about twice the battery life and can be used for other thing's too.

I have had this mental debate many times. I now have a desktop capable of running PI, but I am still at the 'is it worth it stage'. I think this is a bit like the OSC vs mono debate. Good arguments for both sides. At the end of the day, in theory PI is the best AP software. Given the cost of AP as a whole, a bit more for software is not that big a deal really. My main issue is the amount of time needed to learn how to use it correctly - time for me is at a premium. Currently I use Startools, Astro Pixel Processor and Affinity. Could I get better with PI - possibly, but only once I know what I am doing. For me that might be a while🤪

2 hours ago, rickwayne said:

An entry-level DLSR/lens setup on a good mount is a joy to use. The converse...not so much.

An excellent piece of advice. I went down the HEQ5 and ED80 route (which has been good), but actually I now really want to get a wide field lens.

That is a great image - really nice detail. Definitely worth entering the SNR competition.

On 29/09/2021 at 19:24, Rustang said:

I really wish the precious nights could just be with out issue

If it is any consolation I spent 3.5 hours a couple of nights ago trying to get decent star shapes with a new scope and coma corrector - and failed! We all share your pain☹️. Now waiting for the next clear night to try again....

1 hour ago, Ouroboros said:

PS Does anyone know what the object is ringed in the second photo

From looking at Stellarium it would appear to be a bit of extra nebulosity.

2 hours ago, Rustang said:

all I know is that I need a small value but how small is best?.

It will depend on the seeing. Basically adjust to the lowest number you can get on the night.

Just had a quick go at this. I tried to keep as much of the red nebulosity across the field. Maybe a little too colourful...

This was a merger of a de-starred version (starnet++) and the original, some stretching and run through Astroflat pro add-in. Good data to process.

I have used a focus mask and the focus was never perfect. (Admittedly a home made version). I tried using the Bahtinov APT tool to improve it and the results were still not good. I now run the autofocus routine on my focuser which gives a much better result. From memory, APT has a focus aid program which measures the FWHM of a given star - have you tried this? The other thing is to check your subs individually - did it start ok and get worse or was it out from the start? It go fairly cold here last night and the temperature drop could have had an effect.

As Lee_P says, the HEQ5 ED80 combination (which is what I started with) is already over budget - but is a very good set up for starting out. The ED80's regularly come up second hand as do HEQ5 mounts. In fact there are a number of small refractors on astro buy and sell now that would be good options and similar to the ED80.

I have just purchased a TS Photon 6" F4 newtonian which is similar to the 130 PDS and in theory a bit faster. The FL is slightly shorter at 600mm. With coma corrector / reducer you could widen it further. How much of an upgrade this is from a 130 is another question. I brought it to get a faster scope than my ED80. Although I like the refractor at F6.3 it is not fast and to get good images I generally need to get a couple of nights data. I am hoping this can be reduced at F4. It does have a few issues that I need to fully resolve - not least removing the coma to an acceptable level. I currently have a Baader MPCC which I suspect will be pushed at F4 - I might need to get a better one.

Obviously a fast-ish triplet refractor would be considered an upgrade, but if you are getting good images with your current scope it is a lot to shell out.

Lets face it, it is the rule of n+1. I have the same problem😄

I think your idea of using the 130 on the mount supplied with one of the others makes sense to me. The Mak and SCT both have much longer FL's so are probably more suited to lunar or planetary. You heritage 130 will give you a wide field option for other DSO's. I think the difference between 130 and 150mm newts will be marginal.

I have used a 200p on the HEQ5 with the two supplied counterweights without a problem regardless of the finderscope position. Reaching the eyepiece was a different matter......

28 minutes ago, StuartT said:

So only really flats and dark flats need doing then and there (before dismantling the rig, I mean)?

Yes.

51 minutes ago, ollypenrice said:

I'm not sure that bias are useful with CMOS cameras

I was talking about DSLR's really, where they are more beneficial without fixed temperature darks. I would not bother with them for cooled astro camera's

I would agree that out if all calibration frames, flats are most critical. But if you take flats you might as well takes dark flats as most software will easily do both. Darks can be done at anytime so it makes sense to do them for cooled cameras. Bias frames are easy so no excuses there. Therefore you might as well do all of them😁. Jobs a good'n.

17 minutes ago, The Lazy Astronomer said:

Afraid not. To reuse flats, the entire imaging train must be undisturbed between nights

I will not reuse flats as I have to bring the scope indoors between sessions (unless the weather is very well behaved). Even that can cause movement in the dust within the imaging train as I have found out from previous experience.

I use APP and you need to specify which lights and calibration frames are for which session. For darks you can specify all sessions and for which filters. Obviously, if you are using calibration frames for multiple sessions it would not matter. The orientation is not important.

On 18/09/2021 at 14:16, Astro Noodles said:

I agree that these require a white t-shirt as the colour is slightly blue

Does the colour matter? I thought it was not important for flats as long as it was evenly illuminated? I am guessing all LED panels have slightly different tints and wavelengths.

8 hours ago, Robculm said:

wondering why there always seem to be more clear nights when the moon is up?!?!

First rule of AP.🤣

Great result for RGB. I did some NB imaging a couple if nights ago and the gradients were awful. I'd be more than happy with this result.👍

I do not have the scope, but looking at the star shapes it appears to me like an issue with the inbuilt corrector. The flattened section of the stars move round the centre of the image in a similar way to a slightly wrong spaced coma corrector or field flattener. Being a very fast scope getting perfect field correction is not going to be easy. (I am no expert on this, but that is how it appears to me). Is it possible to move the corrector distance in or out slightly which might help? Looking at the spot diagrams for the scope the full field correction is not perfect and with the larger 6200 sensor this will make the problem more noticeable.