Horsehead and Flame Nebulas

This is a picture of the Horsehead area made with my modified Canon 1100D piggybacked onto the C8. I decided to desaturate to get a b/w image.
At the end of the processing a dark narrow band appeared on the photo. I have erased it with the retouch tool... I must understand what it was.

Horsehead and flame nebulae

Modded Canon EOS 1100D piggybacked on a GE mount (no guide). 300mm macro lens, f/5.6, ISO 
800, 90 x 60 sec RAW frames , 30 dark frames, processed with DSS and Gimp.

Here the color version:

M96 Galaxy in Leo

M 96 galaxy

Modded Canon EOS 1100D at the prime focus of C8 (tracking not guided)

70x60 sec frames , 30 dark , ISO 800 

stacked with DSS and elaborated with Gimp

First attempt at the Horsehead Nebula

An excellent seeing last night, so i tried to photograph the Horsehead Nebula with my C8. Unfortunately the 2m focal length without focal reducer is not the best solution...
The result of 50 min integration is very poor, the horse is hardly visible on the right side; the light on the left is the star Alnitak and you can see part of the NGC 2023 at the very bottom:

Horsehead Nebula

Modded Canon EOS 1100D at the prime focus of C8 (tracking not guided)

50x60 sec frames , 10 dark , ISO 800 

stacked with DSS and elaborated with Gimp

M1

Yesterday night work:

                                               M1 Crab Nebula

Modified Canon EOS 1100D at the prime focus of C8 (tracking not guided)

20x120 sec + 30x60 frames , 10 dark , ISO 800.

stacked with DSS and elaborated with Gimp.

Increased integration time...

I have added the two images of Orion (before and after camera modification):

M 42 - Orion Nebula

Unmodified/Modified Canon EOS 1100D at the prime focus of C8 (tracking not guided)

90x60 sec frames , 10 dark , ISO 1600/800 

stacked with DSS and elaborated with Gimp

Modified Canon 1100D

Yesterday I went to Engen (DE) to DSLR AstroTEC, where Tobias converted my Canon taking off the IR filters.
http://www.dslr-astrotec.de/index-eng.html
Now I can photograph the emission nebulae because the HII line is not cut off anymore...
This is my first attempt with the Orion Nebula. You can compare it with the last one made before the conversion.

M 42 - Orion Nebula

Modified Canon EOS 1100D at the prime focus of C8 (tracking not guided)

42x60 sec frames , 10 dark , ISO 800 

stacked with DSS and elaborated with Gimp

Orion Nebula

M 42 - Orion Nebula

Canon EOS 1100D at the prime focus of C8 (tracking not guided)

50x60 sec frames , 10 dark , ISO 1600 

stacked with DSS and elaborated with Gimp