This is a question that some have wondered about. You may be wondering what does this question mean and why should I wonder about it? This would be of interest to you if you have or were thinking of purchasing the MallinCam Micro for Video Astronomy use. Sky conditions were not the best, but served my purpose for this test. Here is the Dumbbell in color using a 17 sec exposure (without using 3D-DNR) on a 5” Celestron with F/6.3 focal reducer and the Micro with a MFR5 focal reducer.
So what’s the deal with using 3D-DNR? This additional setting allows you to average up to five 17 second images in real time, in color. But to use 3D-DNR the AGC must be turned on, which can wash out an image and make it appear to be just a monochrome image. Unless … you also adjust the color settings. I was able to successfully produce an image of the dumbbell with color using 3D-DNR. Below is the Dumbbell with 3D-DNR stacking set to 5, AGC set to high, Brightness set to 2 and Color/WB/ATW R-Y Gain = 250 & B-Y Gain = 250. Here is the result.
And this was from my backyard near a city with a partial moon! Due to the sky conditions, these pictures are certainly not breath-taking, but they do illustrate the Micro can show color when stacking. Just to emphasize the sky conditions, here is the image of the Moon I also captured right after viewing the Dumbbell.
Not great conditions for viewing DSOs, but it is a nice view of the Moon!
Equipment, software and setup
These images were produced with a Celestron C5 (5" spotting scope) with a F/6.3 Focal Reducer and the Micro with a MFR-5 focal reducer on the latest SkyProdigy mount. This is my quick Remote Video Astronomy setup. I can pick it up and take it outside, start an AutoAlign, extend the cable inside to my laptop and be viewing from inside in 10-20 minutes. All these images were viewed and captured while inside.
I have actually written my own software for the Micro with Exposure and Enhancement presets so I can just click on a DSO icon or a Moon icon and it automatically sends the commands to the Micro to change the settings. The software is available for free on my Download tab.
All but the color R-Y gain and B-Y gain can be automatically set using my Micro Extended Control Preset. To include 3D-DNR stacking in the DSO preset, modify the setDSO.txt file as shown below (the setDSO.txt file is in C:\MicroSettings):
Exposure: Normal
Senseup: Off
AGC: High
Lens: x1024
Brightness: 2
Gamma: 0.45
3D-DNR: 5
Monitor: LCD
DPC: Off
The other setting you need to adjust is the Color White Balance which must be set using the control buttons in the Manual section of my application. Click the center button to bring up the Micro's menu on the screen and then the right button to go to the Micro’s Color menu option. Click the Manual buttons to select WB/ATW and set the R-Y gain and B-Y gain settings to 250. Once set, they will remain at that value until manually changed again (you may want to try 200, etc.)
Now clicking on the DSO preset will automatically use the values from your revised DSO Preset file to set the Exposure and Enhance values for stacking in color.
01/10/2015 Update
Although the Micro can produce color images using AGC and stacking, I have found I prefer using the Micro the way I have been using it. I start with AGC on high with no stacking to center my target image. Then I turn AGC off and change the setting to x1024 (or less depending on the brightness of the target) to produce a nice detailed color image. It appears that longer exposures without AGC produce more detailed images (so I do not use a modified setDSO.txt file as described above).
The new release of the MMEC application now has a preset for Center that enables you to quickly change the settings to center your target. Then you can click on the DSO preset to change it to the best setting for more detail . I usually want to invest the additional 20-30 seconds to try the longer exposure with no ACG to see what additional detail it might reveal.
RSS Feed