Telescope Reviews: Color study of the Swan

This the link to the sketch and post of the color study on the Swan. The reason I have repeated it here is because the study of color in an object with astro video cameras is not a quick process. I recommend, of course, knowing your camera and monitor well, because small adjustments can make a substantial difference in what you see. For instance, this sketch was developed using gain that was fairly high (40%) but short integration (mostly 7 seconds and 14 seconds at the end. Integration times do affect color: 2 seconds shows only a hint, 7 seconds shows plenty of detail, 14 seconds shows commensurate detail as 7 seconds but also provides a touch more color brightness. Also, color settings make a big difference. I typically reduce Red by a notch and increase Blue because of the sensitivity of the chip toward red. Red can overwhelm other colors to the eye if no adjustment is made. Last, cloud condition/haze also affect things by increasing reds/pinks that are more easily reflected and get into the background...reducing contrast. One can adjust gain to some extent, but when one starts to lose the ability to see other colors, you know that higher gain is not going to help matters.

We examine the objects using a B&W monitor that still delivers a very nice view (minus color). You can see a little more detail as far as evidence of nebulosity, but any effects of detail rendered by color are typically not noticed in B&W.

Last note: don't be in a hurry. The Swan, for instance, like many nebulae, has lots of reds/pinks, but the detail in differnt hues and the evidence of the purples/blues is not immediately apparent. So, taking the time to examine portions of the object are very worthwhile.

Last, the view on an 80mm was still excellent. While small detail in the nebulous regions was not decipherable, the extended field nebulosity was very good but I did not have enough time to conduct a second sketch. I do notice, however, that the detail in the now-popular 4 inch refractors is quite a bit better than the 3.5 inch variety. Color delivered to screen is sensitive to what I call color density. Light gathering appears to have a minimum to me when I look at a screen. So the 80-mm delivers a nice view; the 102mm delivers a non-linearly better view with almost the same field; the 12.5 inch delivers excellent detail and color but you lose the field.

All these things are helpful to me as lessons learned. Perhaps they will help someone else as well.

Roland