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Daf1983

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Posts posted by Daf1983

  1. Had (yet another🙈) go at Pleiades this week. I upped the integration time (about 150x25s light frames) and used ISO 1600 instead of ISO 800.  I also bought some step down filter rings off Aliexpress to get rid of the big diffraction spikes caused by the lens (thanks @alacantfor the suggestion). 

    I have also invested in Photoshop and the Astronomy tools plug ins to help with processing. These are the final results, the first image being heavily cropped.

    Thanks again everyone for their suggestions and help on this thread. I am now saving up to buy a proper mount and telescope so I can improve my images further.

    PS potrait.png

    PS2.png

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  2. Hello everyone. After all the advice I received on this thread, I've managed to find a couple of hours of cloudless skies to try out this lens again. This time, I took some flat and dark flat frames (not that hard after all), and used some noise reduction plug ins for gimp. I also took more care when stretching the image, checking that the noise wasn't getting to bad as I went along.

    This is my new image of M45, which I think is a slight improvement on the one in the OP.

    Thanks again everyone for their tips and advice🙂

    13_12_20.thumb.png.6981dc847618f62403b02f8b254d29bc.png

    • Like 1
  3. This is very interesting and informative. I also noticed the notches on the diaphragm, wasn't sure if that was normal for vintage lenses, as this is the only one I've used. I also get red halos around bright stars when focusing, and like you, focus by making sure these disappear. 

    I would definitely be interested in a vintage lens thread, as that's all I can afford for the time being👍

  4. 40 minutes ago, Moonshed said:

    “I bought this lens a few weeks ago. This is what I've managed with it so far. Don't be put off with these images though, as I'm a complete novice, and my processing skills aren't the best.”

    Hi Daf1983, there’s nothing wrong with your processing skills!

    Thanks for your kind words. I would have been overjoyed with those images when starting a few months back, but I suppose you become more self critical as you gain some experience. 

  5. 8 hours ago, rickwayne said:

    Until I actually built myself an autofocuser, a Bahtinov mask was pretty much a mission-critical item for me. You get to a point, focusing by eye, where you can't really tell that moving the ring is having any effect. But the Bahtinov knows. I personally had some trouble judging when the spike was exactly centered, others don't seem to struggle with that. But any movement at all of the focuser has a visible effect on the spike location.

    The other bit of advice I'd give is not to go for a really bright star, you will often see a cleaner pattern on dimmer stars. The fatter spikes from brighter stars obscure the last little bit of accuracy. A bright star is great for getting in the ballpark, then fine-tune with a dimmer one. Note that focus can vary across the field, so if you use a bright star in the center and try to fine-tune with a dim one in the corner...that way madness lies, my friend.

    Thanks for the advice. I will definitely look into some kind of mask to aid with focusing, as I must admit, there is some degree of guessing going on with my current approach. 

    I've read that Y lord is maybe more suitable for dslr lenses, as they let more light in? They also look easier to make than a bahtinov mask(don't want to be spending more money at the minute🙈)

  6. 9 minutes ago, happy-kat said:

    Yes it makes it easier but need a very bright star, could make a simple Y Lord mask out of cardboard.

    Personally I use DSL Controller and an Android device makes things so much easier with the Canon 1100d.

    There is an Infinity YouTube on processing Orion by one of Serif's staff, that is good to follow as GIMP likely do it all.

    Also there is in Infinity StarGaZine video if you look through the various StarGaZine episodes forum on here. 

    I've thought about making a Y lord mask, it might be worth a shot, and I will have a look at the videos you mentioned when I have time. I followed one of Serif's (I think) when trying to process andromeda a couple a months back.

    Regarding a dslr controller and android app, how would that aid focusing?(excuse my ignorance)

    Thanks again

  7. 4 minutes ago, rickwayne said:

    Orion shot looks much better focused than the Pleiades. What are you using for focus assist?

    A simple brute-force antinoise tactic: simply to pile on the integration time. But it's a square-root relationship, so four times the integration merely doubles the signal/noise ratio.

    At the minute, I'm focusing using live view at x10 magnification. I suppose a bahtinov mask would help?

  8. 5 minutes ago, happy-kat said:

    The process is also possible to replicate using GIMP. I may find a link later

    Thanks again, everyone has been very helpful! Up to about 2 months ago, I had done zero image processing. Feel like I have learned a lot in that time(mostly from reading and getting advice on here), but also feel I have a LOT still to learn

  9. 1 hour ago, Aramcheck said:

    It depends on the software you're using, but the idea is to mask off areas of high signal & to blur the background. In Pixinsight I use the MultiscaleLinearTransform (MLT) tool on the linear image & ACDNR once the image has been stretched & is non-linear. At the end of processing I sometimes then use a PixelMath expression to try to reduce any remaining DLSR mottling.

    The screen grab shows a before & after image of the MLT process on a small area of background.

    Cheers
    Ivor

    noise_example.JPG

    I've only used free software to do my processing so far (gimp and siril). I'm guessing they don't have the features you've described above? 

  10. 56 minutes ago, alacant said:

    They're only cheap items and it saves you the hassle of blu-tak and glue DIY.

    For f5.6, the nearest I could get without a longer search, is this and this which gives you an aperture of 28mm; around f5. For exactly 5.6 you need to step down to 24mm.

    HTH.

     

    Thank you for taking the time to look for them👍 Where/how do they attach to the lens? Does it have to be specific type for a specific lens? (Sorry for all the questions)

  11. Thanks everyone👍 I'll have a go at taking some flats next time. 

    15 minutes ago, alacant said:

    Hi

    Excellent shots. Some of the old lenses are really good. To lose the spikes, leave the lens wide open and use a 49mm to 42mm step down filter ring.

    There are some good denoising algorithms in modern software. This is the m45 jpg converted to tif using StarTools' denoise. The latter can also produce excellent synthetic flat and bias for you. Good for when you've forgotten or just can't be bothered!

    Cheers

     

    Thanks for that, will have a go with that software. Where could I get hold of a filter ring?

  12. 2 minutes ago, happy-kat said:

    Flats and dark flats you could also do and these I find help an image background noise.

    I thought someone would suggest this. I've been putting off doing flats, mainly because I don't really know how to, and it seems very fiddly. I will have to look into it and give it a go😁

  13. A couple of clear nights gave me chance to try out my new Carl Zeiss Jena 135mm lens. Managed to capture pleiades and Orion belt with m42. My other equipment include the omegon minitrack lx2 and a canon 600d. 

    Pleiades was taken at iso800, and I took about 45 light frames, which were 25 seconds each, also took 15 dark and bias frames.

    Orion was taken at iso 1600, light frames 10 seconds x100 along with dark and bias again. Both pictures were stacked in dss and processed with siril and gimp.

    Although far from perfect, as a complete novice, I'm quite happy with the results. I'm also pleased with the performance of the lens, considering what I paid for it. Although it does need stopping down to f5.6 to get decent results.

    My main issue at the minute seems to be how noisy the images are. I assume I need to up the total exposure time to improve this?

    Any suggestions and constructive criticism

     are welcome.😁

     

     

     

    Polish_20201128_223459049.jpg

    pleiades 26.11.20.jpg

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