Meade DSI

My name is Slawomir Bucki and I have posted a couple of reviews on Cloudy Nights beforehand. I have been a visual amateur stargazer for many years and have some limited experience with conventional film astrophotography. I have never done CCD astrophotography before the purchase of the Meade DSI Currently I am located in southeaster Louisiana, few miles away from New Orleans.

I purchased the Meade DSI from Anacortes Telescope and Wild Bird over the Internet less than two weeks ago. The following review and attached pictures are based on my first, and so far only, night out with the Meade DSI.

Highlights:

At less than $100, the Meade DSI is an incredible bargain and well worth the money. It is easy to use and one can make decent pictures on the first night out (which is very rewarding and energizing to continue trying again and again). The package is a good combination of highly functional software and decent hardware, that work together very well ? everything you need comes in a single package and does not need any extra accessories (except your scope, mount and computer), nor lengthy configuration and adjustment process. Congratulations to Meade for developing such an affordable package to introduce us to the world of CCD imaging.

The equipment I used is:

Skywatcher shorttube 80mm f/5 achromatic refractor (identical to the one sold under many brand names: Orion, Celestron, etc.)
Vixen GP mount with motorized RA drive
HP Pavilion dx 1000 laptop with Windows XP

I took all the pictures unguided, but with the scope in good polar alignment (within +/ 10 minutes from true north) ? side comment: the Vixen GP is a great mount. The session lasted for about 3 hours (including set up time) and I took pictures of Jupiter, M13, M22, M27 and M57. I don't have GoTo, so this time includes manually finding and aligning precisely the object for the astrophoto, plus the time necessary to refocus the scope between the eyepiece and the camera. I did not use a piggyback setup with my other scope, but I will do it the next time to save time. My observing location is far from ideal ? I'm in southeastern Louisiana and took the pictures in 90 deg heat, with over 80% relative humidity, at a suburban location with a fair amount of light pollution, from my driveway nice illuminated with sodium street lights.

Software:

The software installed cleanly, following the steps provided on the leaflet that came with the camera. There were no issues with the installation, and the camera worked right away as described. However, when I reconnected the camera a couple of hours later (and after turning the computer off and on), I had to reinstall the driver again from the CDROM. This has happened only once, and since that time the camera and the computer have been "talking" to each other without problem every time I connected them. Also, during the picture taking session I realized that some software controls stop working after taking a series of exposure, making it impossible to take two pictures in a row. The solution is to close and reopen the imaging program again ? it only takes few seconds and I don't see it as a major problem. Frankly, I don't know if this is a software bug or I am doing something wrong, given that my experience with the product is just a few hours. My general opinion about the software is pretty good, and I like that the picture taking and processing can be done with the same program and in realtime. I can't compare the Meade software with other products because I have not used any, but I find the degree of control over exposure, as well as the image processing controls to be highly functional, effective, intuitive and easy to use. More below under Image Processing paragraph.

Using the camera: I took the pictures following (loosely) the steps outlined in the manual of the product (which I printed beforehand). I will only mention below some highlight from my experience, and refer the reader to the Meade manual for more information on the sequence of steps to take images.

Focusing is somewhat cumbersome. The Magic Eye control works well in daylight, but I didn't find it very helpful at night. Instead, I focus the scope using a 25mm eyepiece (that I parafocalized beforehand) to achieve coarse focus, and then finetune the focus in very small steps using the LIVE function. Given that the LIVE function updates the image on the computer screen only once per second, and one has to account for the shaking and movement induced on the scope while focusing it, it can take a couple of minutes to achieve good focus.

Taking and stacking multiple exposures: Meade manual says that one should stack approx. 50 images and suggests starting with 15 sec exposure to achieve a good image of a deep space object. Personally I found that I could get better pictures with longer exposure time (30 sec and 1 minute), but did not notice any substantial improvement in image quality after stacking between 4 and 10 images. Yes, stacking at least 4 and up to 10 images delivers much better image than a single exposure, but beyond that number I didn't notice any difference at all. Maybe with more experience, and on dimmer, more challenging objects the difference will become more apparent, but starting with 510 exposures is OK, and saves a lot of time. The tracking function of the imaging software is very useful and I did not observe any guiding errors on the stacked pictures (but they were apparent on the pictures I took by mistake without the tracking function).

Processing the image: I achieved best results by using the following sequence:

1) Take a Preview image using same exposure time you will use later to stack the images. You can play with different exposure times at that step.
2) Adjust the image using the histogram controls. It is the most useful control to improve the image appearance. I did not find the contrast and shadow enhance controls very useful ? they make bright features of the object more prominent and make subtle details disappear. Maybe they will be more useful on planets and the Moon, but for deep space objects I found the histogram controls to be the tool of choice
3) Take and stack the images, and make final adjustment on the image quality with the histogram controls.

Other comments:

The dark subtract function works well, I have not observed any background noise on the stacked images, even after trying exposure times as long as 23 minutes. Print the manual and play with the camera in daylight to get used to the controls before attempting a night astrophotography session. Pick a low power eyepiece and parafocalize it with the camera using the provided ring ? it will help a lot later to find objects and refocus the scope.

Bottom line: Great value product, well worth the purchase. Excellent package to introduce oneself to CCD imaging. And with such a low price, it won't be a regretful throwaway even if you decide to upgrade to a high end CCD imager later. Highly recommended.