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M13 from BMVO
Gary Trapuzzano

Two weeks ago I met Al Lamperti and Joe Lamb up at BMVO for a night out under clear, transparent skies. I decided to try using my old but trusty Celestron C9.25 as the OTA in my astrophotgraphy setup to see how it would perform with a recently acquired Starizona 0.63x focal reducer/flattener. I chose M13 as my target and was pleasantly by the results.

Camera: ZWO ASI2600MC-Pro (cooled to -10ºC)

OTA: Celestron C9.25 with Starizona 0.63x Focal Reducer/Field Flattener (F.L. ~1,600mm)

Mount: iOptron CEM40

Filter: UV/IR Block

Integration: 65 mins (13 x 5min subs)

Pre & Post Processing: PixInsight

Image Presentation Template: Photoshop CS5.1

Clear skies,


Daniel Stern
Hi Gary,
Very nice. I especially like the depth of star colors.


Gary Trapuzzano

Thank you Dan. I used the LRGBCombination tool in PixInsight with the saturation control set to 0.4 to apply the luminance channel only back to the RGB image. I've found this technique to be a good way to increase saturation in a controlled manner.

Clear skies,


Joseph Lamb

Beautiful shot. I agree with Dan. Magnificent colors.


Gary Trapuzzano
Thank you Joe!


Lou Varvarezis


Very nice example of M13, I love how it seems to jump right out of the page almost like you're really there. It's one of the more vivid/alive images of M13 I have seen recently. Exceptionally well done.


Canon EOS Rebel XS (full spectrum mod)

Astronomik CLS CCD

Orion thin off axis guider

QHY5L-II M guide camera

Celestron CGX,Edge HD 8,0.7x focal reducer

Optec TCF-Leo focuser

Gary Trapuzzano
Thank you Lou.  Much appreciated!

I think what you're referring to might be a result of intentionally increasing the black point to reduce the background sky.  I usually leave the background sky more on the gray side so as to not lose low level detail, but in this case I didn't do that in order to get more contrast between the star colors and background.  Doing that seemed to give the image more "punch".


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