M8 with 300D mod

[NickRose2006]

Last night I got a chance to test out my 300D that I modded to a full spectrum camera. The target I went for was M8 the Lagoon Nebula. Since I decided not to replace the filter glass I had to take several test shots to get a good focus. I was not pleased with the focus, don't know if it was the bad seeing of at least 2 or UV/IR light. Are the stars bloated because of the bad seeing or UV/IR even though Reflectors are supposed to focus all wavelengths? Anyway I was surprised that it only took 15sec to for it too show in the picture, it only took 33s to get about halfway to the middle of the histogram.

Target: Lagoon Nebula/M8

Telescope: Celestron SP-C6

Mount: Vixen Super Polaris

Unguided

Camera: Full Spectrum Canon 300D Rebel

Subs: 2x15s, 21x33s lights at ISO 800, 20x30s Darks, 20 Flats

[roundycat]

Looks like a focus issue to me. The bloated/saturated stars are most likely down to a slightly careless stretching of the data. Try it again but do not let the white point move at all.

Dennis

[skywatcher1701]

I have just got a 300D, and looking at your photo, it gives me hope that I will be able to get some sort of result, even though mine is a standard model.

I know i will have to take longer or lots of shot exposures to get some thing like this, but it looks good, with a little more advice from the experts on here you should get a great end result. well done

[whirlpool5194]

Looks ok from where I'm sitting. The low elevation won't help unless your in Oz.....

Wp

[NickRose2006]

Ok so I re-did the image two times the first was to do the levels again and then the second is that I looked at the subs and took out the ones that were not as sharp. That reduced it from 23 subs to 13, which then produced more noise, but I think the image is slightly sharper. I also include a single sub, the only thing I did was to crop it and resize. Most of the other 12 subs had slightly larger stars. Also I noticed that my collimation is little off.

1st Pic: The single sub that was the sharpest and smaller stars.

2nd Pic: First redo which is just levels and curves.

3rd Pic: Second redo which is a new stack with just 13 of the best subs.

[fatwoul]

I'd agree with the comments about focus, but I'd also say that the gradations of nebulosity you've got are lovely. Have you got a Bahtinov mask? They make such a difference to focussing. You could try making one out of cardboard before committing to buying one. I used a scalpel cut one from thin modelling plastic I bought from Antics, which served me well for months.

[NickRose2006]

I'd agree with the comments about focus, but I'd also say that the gradations of nebulosity you've got are lovely. Have you got a Bahtinov mask? They make such a difference to focussing. You could try making one out of cardboard before committing to buying one. I used a scalpel cut one from thin modelling plastic I bought from Antics, which served me well for months.

Yes I did make one but for some reason I decided to try and change the focus because I was getting big stars. I might be going out again tonight to do some more testing and to get better subs of M8.

[NickRose2006]

Last night I went for M8 again and everything worked like a dream. I fixed the collimation, which was off just a tiny bit and the I used the mask again since the stars were not bloated this time. Also the seeing was much better it was a 4 unlike the other night when it was a 1 or 2. So I have no idea what fixed the bloated stars. Only had time to get 13 good subs, so its quite noise. I added two different versions, the second one has a darker background.

Target: Lagoon Nebula/M8

Telescope: Celestron SP-C6

Mount: Vixen Super Polaris

Guided

Camera: Full Spectrum Canon 300D Rebel

Subs: 5x120s, 8x40s lights at ISO 800, 9x120s Darks, 9 Flats

[roundycat]

I nicked the second one and did some work with Curves to get rid of the green and lower the background as well as raising the contrast slightly. Then Neat Image to reduce some of the noise, not an ideal solution on a jpeg as the compression artefacts come out as noise.

Dennis

[NickRose2006]

I nicked the second one and did some work with Curves to get rid of the green and lower the background as well as raising the contrast slightly. Then Neat Image to reduce some of the noise, not an ideal solution on a jpeg as the compression artefacts come out as noise.

Dennis

So with that I decided to redo the image and I think it came out better, at least the background is darker. Hopefully I didn't clip the dark, at least my histogram says I didn't.

[Daniel-K]

this is very good and shows that you dont need to spend mega bucks to get into AP you have done well very nice picture