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Image Challenge March/April
Lou Varvarezis

Hello everyone,

Thank you to all who contributed images for the December and January challenges. We had some fantastic examples submitted of Orion and the Rosette nebula by several club members. It’s amazing how much of the sky can be captured with a simple DSLR camera with just a tiny bit of patience. We did not have a challenge for the month of February to work on this year, however, now we have entered galaxy season and that is about to change.

Soon, there will be many possible targets ideally positioned in the sky. This time, I thought it might be best to take a different approach and make it easier for a wider range of focal lengths to take on this challenge. Rather than choosing a specific galaxy or group of galaxies to target, instead I would like to leave that part of the challenge up to the individual astrophotographer. You choose a which galaxy or group of galaxies to photograph. However, I would like to suggest the following guidelines on how to approach this challenge.

1. To ensure the best view through the atmosphere, choose a target that will be transiting the meridian during the time data is being collected. The closer to the meridian when collecting data, the better.

2. Choose a focal length that works well with your camera and sensor. For example, as far as focal length is concerned, Markarian's chain is a great target to pair with shorter focal length systems (<600mm). Whereas specific targets like M 104 (The Sombrero Galaxy), NGC 4435/NGC 4438 (The Eyes Galaxies) or 4038/NGC 4039 (The Antennae Galaxies), etc... are more appropriate targets for longer focal length systems. That still leaves pixel size to consider (see next paragraph).

3. Use any tool or software available to help select and frame up a target. Here is the URL to a free web-based resource Once in the toolbox, click on the equipment option (the little camera on the upper left corner) to select your gear from the drop-down menus. The field of view will be outlined in green box and will also provide you with the Dawes limit to help you find the best focal length to use with your sensor and pixel size. Follow this link for more detailed instructions

4. Remember, be patient and wait for clear Moonless nights to collect data -- unless you use an appropriate narrow band filter, the light from the Moon will swallow up your data.

5. Most importantly, remember to be patient and that you're having fun, especially when something goes wrong.

Good luck and clear skies,


Hari Doraisamy

Here's my wide field attempt at imaging Messier 81 and 82. It is my first attempt at the pair. I think I need more light frames to get more data

Canon EOS Rebel T6 with MSM tracker with a 200mm Pentax telephoto lens

109 light subs @15 sec each for a total of 27 min

15 darks, bias and flats

Taken over 2 nights (March 3 and 5) in Willistown Twp

I am still struggling to see this visually through my 8" Nexstar scope, but that's a different topic :)

Hari Doraisamy

Here's my attempt to get the whirlpool galaxy (Messier 51) as a widefield image. The inter-galactic interaction is visible. However, I still need to improve my polar alignment and see some coma.

Taken over 2 nights (Mar 29/30) from Rehoboth beach with a waning moon at 98% :)

Equipment: Pentax 200mm lens + Canon EOS Rebel T6 + Move Shoot Move star tracker

Total exposure time: 42 min at ISO 1600 at f/5.6

Processed with DSS and enhanced with Photoshop.

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