AnonymousAnimosity

Hello, I have recently upgraded my astrophotography setup with a modified canon 100D, a vintage zeiss 135mm f3.5 lens and the optolong l-enhance filter. My previous camera did not support wired intervalometers, now I can finally just leave it outside at night.

I have been lucky enough to find clear skies at home around the new moon (bortle 4 zone).

The first target was the cygnus region, shot with a 50mm/f2.5 canon lens (m42 to EF adapter hadn't arrived yet) at f3.2.  I took 36 3 minute lights at ISO 400. Looking at the red channel alone there is much more contrast and detail which I can't match in the full image.

After receiving the adapter I set out to shoot the elephant's trunk nebula. Over three nights of battle with the clouds I shot about 250 lights, mostly 2 minutes and one hour or so at 1.5 minutes.

I expected processing to be a breeze but it turned out more difficult than expected, I struggle lifting the nebula from the background. I have also noticed a weird gradient in the image, which I assume to be vignetting (i woke up at 4am to turn off the camera and forgot to take flats), is that correct? I think it might also be due to thin clouds that I did not noticed when I sorted the pictures. I should be able to remove it taking some flats now. I am not very satisfied with the result, this was my processing workflow:

1) Siril:

• preprocessing and stacking
• colour calibration
• background extraction (seems to work better than startools' wipe module for wide fields of view)

2) Startools:

• autodevelop
• bin 50%
• sharp and contrast module
• shrink stars
• entropy module (lifts up hydrogen alpha)
• noise reduction
• bump in saturation

Any tips or leads? The upper right portion of the background looks particularly hideous.

Yesterday the l-enhance clip-in filter arrived and I did a quick test at 50mm. The target was again the cygnus region, about one hour of 5-6 minute subs at ISO 800-1600. I have stretched it very conservatively because there seems to be a lot of noise, today I will do some tests to determine the optimal ISO for this camera. I appreciate the lack of stars but I expected more nebulosity, do I just need more data?

Yesterday night the sky was clear for a couple of hours so I got a chance to test my new modified Canon 100D.  I bought a 135mm f3.5 carl zeiss jena lens but the adapter hadn't yet arrived so I shot with a canon 50mm at f4.

Here are 36 180s light frames of cygnus shot at ISO 400.

Processing was done in siril and startools.

I am not fully satisfied with the outcome but I can't quite figure out what is missing here (apart from more hours of integration time, I was cut short by clouds).  Any leads?

I took 50 or so flat frames (camera in AV, smartphone with white screen in front of lens) but I noticed that processing with flats led to more gradients in the final image. Could this be due to uneven brightness of the screen?

Thank you for the input, I think I will buy either the optolong UHC or the l-enhance if I feel like spending more.

I have done some more research on filters but I have yet to make up my mind on which one to buy.

Is a UHC filter narrow enough to allow for acceptable results with a full moon?

If I understand correctly the advantages of clip-in filters are blocking dust from entering the sensor and not needing adapters to use with camera lenses,  is there something else? I noticed that sometimes 2" versions are cheaper.

I have seen the optolong l-enhance mentioned frequently as a good filter for DSLR shooting, but the price is a bit steep, would the difference be significant compared to a cheaper UHC?

Concerning UHC filters, I have found an Optolong for about 60€, while the Astronomik model is almost double the price (used). I know that the latter has a narrower band and thus cuts out more light pollution, but is it worth it the higher cost?

I am open to suggestions of products I might have missed.

45 minutes ago, david_taurus83 said:

If you can shoot 3 minutes then your LP can't be that bad? Why do you think you would benefit from a filter?

In my hometown I have fairly dark skies (granted the 3 minute shots were on a new moon and at f6.3), but I only visit about once a month and generally either the weather is bad or the moon is too full. The city where I study and live most of the time is much more light polluted, I have made some attempts but they turned out unsatisfactory.

3 minutes ago, david_taurus83 said:

Will you be using a telescope or camera lens? The IDAS filters are very good and give a good colour balance but they are the most expensive. The D2 version is supposed to block out some LED light pollution so might be worth looking at that if you have LED street lights in the area. You could use narrowband filters like an Ha but it would mean longer exposures. The more popular choice these days is to use a duo band or tri band filter that pass mainly the traditional narrowband wavelengths of Ha and OIII. This will give you a colour image of emission nebula with the added benefit of blocking out light pollution. Again, it does mean longer exposures. Your chosen focal length will determine how long you can do on your Star Adventurer.

Thank you for the reply, I plan to use a camera lens (on my current setup I use a 70-200, I will borrow something similar for the canon) and eventually upgrade to a small telescope when I find a good deal. I aim for widefield views of deep sky objects. With a good polar alignment I have managed to shoot past 3 minutes at 200mm with about 40% discarded due to periodic error.

I will do some research on the different filters, it seems that a light pollution filter or duo/tri band woud be more efficient than single bands as it would all the pixels, right?

Hello, I am considering the purchase of a full-spectrum modded canon DSLR (I'm not set on a specific model, I found the 1200D for a good price) for deep sky astrophotography. Because of artificial and lunar light pollution I don't get to shoot as often as I'd like, and it seems that filters of some sort would allow me to collect data much more often. However, I am not sure whether it would be best to buy a hydrogen-alpha filter (and eventually add OIII and SII later on) or something like the IDAS D1.

I understand the downsides of narrowband imaging (processing the different channels, longer times), so it seems that a light pollution filter would be much easier to operate, but how would the results compare?

Another concern I have is that narrowband may be unsuited to my  mount (star adventurer) due to the lack of GoTo. Is that so or is the difficulty in finding objects manageable?

Thank you for your help

Here's my first attempt at M42 with a 70-200 f4 lens (at 200mm) from a bortle 4 zone.

f6.3, ISO 800, 45x90" lights, no flats (I completely forgot, therefore it was necessary to crop the image drastically due to dust particles on the sensor)

stacked in DSS and processed in Startools. I am going to shoot this again soon aiming for more integration time, hoping to bring out some dust.

50 minutes ago, rickwayne said:

That's a beautiful M31. Did you do localized contrast enhancement to bring out the dust lanes, or is this just overall stretching?

I did play around a bit with the contrast module in startools to make them pop out.

Hi everybody, since my first post on this forum I have upgraded my setup with a Star adventurer and an old pentax 70-200 f4 lens. I haven't had much time at home (bortle 4) since february due to university and work in the summer, these are the pictures I've managed to capture with my new gear. All the images were stacked in DSS and processed with startools. The workflow was very similar for all of them: autodev, crop, bin, wipe, autodev, sharp, contrast, hdr, colour and noise reduction.

This is a widefield view of the cygnus constellation, I was hoping to center it around sadr but I didn't realize the framing was off until I processed the image. If I remember correctly it's a stack of 45-60 60s shots at f3.2 with a 50mm f1.8 lens. It was my first time processing a region without large bright objects, there is definitely a big margin for improvement in the processing of this type of data.

Another 50mm shot, this time about 90 minutes of total exposure in 60" shots. I was hoping to capture some of the dust between the pleiades and the california nebula, surely more data would have helped but again the processing can be improved.

This was my first attempt with the 200mm lens, about 100 minutes of total data, 60" shots. This lens suffers from severe aberration of all kinds, therefore this was shot at f8. It was definitely stretched too far, because I was trying to pull out more detail than less than 2 hours of data can offer.

This is yesterday's attempt at andromeda, captured at 200mm, f6.3, ISO 1600. Only 60 minutes of total data, 30x120s lights and some flats. I'm fairly satisfied, although I can tell that the colour balance is not optimal (most stars are white-blueish). This too is stretched too far, the next time I shoot this I will be aiming for at least 2 hours of total exposure. Speaking of that, as of now I feel limited by the lack of an intervalometer plug in my camera (pentax k-s1), which means I use my phone as a remote. In the near future I'll either find a way to tape the phone to the tripod in a way that the IR blaster's always pointing at the camera, or look into building a simple IR intervalometer. 

I'm open for advice on how to optimize my photographs, in both acquisition and processing. I will update this post with links to the stacked files in case any of you want to try doing a better job with my data.

Thanks for your attention and clear skies for all!

On 24/04/2019 at 21:34, antaeus said:

I like how you managed the colors in both pictures. This is something I never get it right. What ISO did you use? Nice read noise reduction on both pictures. Congratulations! 

Cezar

Thank you, I used ISO 1600 for all the shots. Compared to my processing attempts with GIMP, Startools proved to be far quicker for noise reduction and a good colour balance. 

25 minutes ago, happy-kat said:

They've come out very clear what the targets are. Did it take a long time for DSS to process that amount of images? Also your stars are nice and tight did you stop the lens down or is that not the nifty fifty?

Yeah, my laptop isn't the fastest so it took about three hours if I remember correctly. The lens was stopped down to f2.8, but I also managed to shrink them slightly with Startools. 

These two were taken with a 50mm 1.8 lens on an unmodded Pentax K-S1 camera and an old Manfrotto tripod. 

I shot about 1300x4" lights for Andromeda and 1100x4" for Orion. About 30-40 darks and flats each. Stacked them in DSS and processed with Startools. 

Any criticism is welcome!