Kenboy

apparently the canon 50mm f1.8 is best at around f/2.8?? 

what f ratio shall I use?? 

2 hours ago, Rustang said:

Make a cone around the lens using card, funky foam or similar to act as a dew shield!? 🤔

ooo thx I can try this

2 hours ago, PeterCPC said:

I would go with ISO800. You'll have to set the exposure time depending on your histogram but if we are talking non tracking then you will be limited to maybe 15 secs. Stack as many as you can. Hairdryer on lens maybe.

Sorry I didn't mention. I am using a SA star tracker. So ISO 800, with 1 minute exposures x 30 sounds ok? 

Hi all! 

Looks like finally some clear moonless skies near me tonight

I've got a beginner setup and just wanted to ask few quick questions 

Setup: Astro modified Canon 550d, Svbony CLS clip filter, Canon 50mm F1.8STM lens in Bortle 5 skies. 

What ISO and exposure length would you recommend to image at? how many shots to stack?

Any ideas how I can prevent mist on my lens? (it's going to be -8 degrees, and I don't have any warmer)

thx so much 

https://www.amazon.co.uk/Svbony-Pollution-Broadband-Astronomical-Photography/dp/B07GB3QFTK/ref=sr_1_3?crid=35V84CNR2GS93&dchild=1&keywords=astrophotography%2Bdslr%2Bfilter&qid=1612021571&sprefix=astrophoto%2Caps%2C161&sr=8-3&th=1

is the above a good idea? 

Hi all

Looking for a filter suggestion for imaging DSOs in Bortle 5 skies 

I have an Astro modded Canon 550d +  canon EF 50 mm f/1.8 STM prime lens on a SA star tracker. 

Budget is < £100, any cheap filter that would bring about more DSO detail? 

thanks!! 

awesome thx, do I have to choose filter removal or full spectrum? I'll only be using it for astrophotography. 

On 01/12/2020 at 12:12, KP82 said:

Since you've got the luxury of Bortle 4 skies nearby, the best option for you is to get your DSLR astro-modded and you will get the best results without any filters.

On 01/12/2020 at 12:23, PeterCPC said:

+1 for astro modding.

Ok thx !

how do I go about getting this done? 

Hi all 

I'm looking to get more detail and nebulosity from my small setup, need some advice buying a camera filter

I'm using an un-modded Canon 550D + Canon 50mm f/1.8 STM lens on a Star Adventurer mount. I have Bortle 4 skies nearby. (i don't have a scope atm) 

Budget is ~ £100 

Any ideas for a filter that would improve my setup? or shall I just aim to get the camera modded? 

Thanks!

I am hoping to get something close to this? (but this is with an expensive Ha filter!) 

Hi all 

I've got an unmodified DSLR and 50mm F/1.8 STM lens under Bortle 5 skies.

Any suggestion for a LP filter to bring out more nebulosity? Budget is under £60

I was thinking between Svbony CLS vs UHC EOS-C filter, or any other suggestions would be appreciated? 

thanks!

56 minutes ago, wimvb said:

I've downloaded your data, and am playing with it in both PI and GIMP.

In GIMP I cheated a little, because I first removed the gradient in PI and also did colour calibration there. But after that I moved the image to GIMP and played with levels and curves.

In levels:

• midpoint slider to about 25% (so midway between its original position and the black point).
• adjusted the black point (left slider) to just below the foot of the histogram, so as not to clip any pixels.

Repeated this procedure twice.

Then went to Curves and applied a gentle S-curve, lowering the curve a little just at the peak of the histogram, and raised it a little at about 60-65% of the hoizontal axis.

In curves, targeting the red channel only:

I put a marker on the curve at 25% and at 75% to fix the dark areas bright areas. This to make sure I didn't end up with a colour cast in the background or pink stars. I then raised the middle section a little to enhance the nebulosity.

Finally I rescaled the image to 50% and saved as jpeg.

This is my first time using GIMP for image processing, so be gentle with me. 😋

And the image after pixinsight (arcsinh stretch, lifting the nebulosity with exponential transform, and star reduction. No resampling)

 

(click on the images to enlarge)

2nd one looks really nice! Thanks 

Hi all,

I took this last night, finding difficult to bring much out of it, not sure if it's editing or the picture itself? 

I've messed around with the levels/curves function, but it appears too bright

Would anyone be able to edit this on GIMP (or something else) and explain briefly how you did it? 

I'm attaching the un-stretched stacked version 

Thanks! 

10-07-20 astropic 2.TIF

On 05/07/2020 at 15:07, happy-kat said:

Though that focal length on the Moon might be interesting and exposures there would be pretty short

Turns out, even with 15mm eyepiece and 3x Barlow, I couldn't get focus on the Moon. 😛

7 hours ago, Aramcheck said:

I think you'll need to provide the stacked but unstretched image of the RAW files, as this one has already been stretched. You would normally try to removed the light pollution background whilst the data was still in it's linear (unstretched) form.

It's always better to have more exposures (and/or longer exposures if the mount tracking will allow).

Also how dark was the sky? At the moment here in the UK there is only a small window of Nautical Darkness & where I am it never reaches 'Astro darkness' at the moment.

If the DLSR is un-modified that will also affect how much nebulosity you can capture, but that will vary between targets.

Cheers
Ivor

I've attached the unstretched image

How is light pollution removed on unstretched files? is that gradient removal? 

Astropic 05-07.TIF

6 hours ago, bobro said:

For straightforward processing Doug German's videos are a great start. He doesn't use GIMP, though GIMP has the same sort of processing functions Doug uses.

For gradient removal see: https://www.youtube.com/watch?v=yTEVMH_WE80

Below is your image processed with the methods Doug proposes (gradient removal and star masking) using GIMP, plus saturation increase and stretching. I'm no expert at processing and others will do much better, but it gives an idea of what can be done with the image - some of the nebulosity around Sadr is becoming visible.

Of course a night with less moonlight will help as image noise will be less.

 Ah yes, thanks very much! really helpful

Hi all,

I took this last night with a DSLR and mount (lot of moonlight!)

I stacked 30 x 1 min exposures 

Can anyone show me how to get any more details from this pic? how do I bring out any nebulae etc? 

I'm using GIMP curves function, but nothing really shows up 😕 (except the obvious light pollution) 

thanks !  

Astropic 05-07 n.TIF

Thanks both

Really helpful !

I think I'll just try my DSLR + 50mm F/1.8 lens and see what I can get 

Hey all,

I've a Celestron 76eq scope (3" aperture, 700mm focal length), DSLR and star adventurer mount. Trying to do some AP with this setup (I know, not ideal :P, but want to give it a shot anyways)

I'm finding it quite difficult to get focus, I can manage a clear picture by connecting a T adaptor, 15mm eye piece and a 3x barlow 

But I think this would give me way too much magnification for DSOs, and also put a strain on my tracking.

Any suggestions on how I can modify my setup to maintain focus and get reasonable pics? 

Thanks !

3 minutes ago, Kyle Allen said:

Do you mean this one?

https://www.amazon.co.uk/Mystery-Telescope-Adapter-Extension-Mirrorless/dp/B01IN6N0XG/ref=pd_lpo_421_t_0/261-8212470-6264061?_encoding=UTF8&pd_rd_i=B01IN6N0XG&pd_rd_r=d46405a1-ab19-42db-8c6f-6fae350e59ba&pd_rd_w=yhr4k&pd_rd_wg=stnHM&pf_rd_p=7b8e3b03-1439-4489-abd4-4a138cf4eca6&pf_rd_r=G31H6J5GK2CJWQ51MYWC&psc=1&refRID=G31H6J5GK2CJWQ51MYWC

yeah am I gonna have to buy something like that? 

currently i only have the t adaptor i linked in the original post

12 minutes ago, Kyle Allen said:

Yes, the one you linked to earlier allows you to use an eyepiece so you will be able to reach focus. 

I have that T adaptor, but I'm not able to attach it to my 15mm Celestron Omni eye piece and then onto the scope

I am able to focus the image if I look through my 15 mm eye piece with my DSLR - is it possible to buy an adaptor that can allow for an eye piece to be slotted into it? 

yes I can't reach focus, can't move the focus far in enough

what can I do? 

might focus on stars though? idk

I have setup the t adaptor + 3x Barlow to this telescope, and when I focus on far away objects they are still blurry!!

Any help? 😕