symmetal

You can set binning in a CMOS camera but it is effectively just software binning applied after the sensor has been read so the only 'benefit' is a smaller file size and therefore quicker download. Alan

Using higher gain (2x unity is often quoted) for narrowband may mathematically give you a slight S/N advantage I believe over unity gain so there's no harm in doing that. It's more a case of the extra hassle in having to keep track of what settings are being used for different filters that I use unity gain for everything. I think it's worth just using one offset setting for all to gain settings you use to remove one variability, I use 56 to just avoid clipping blacks, vlaiv uses around 64 I think to be doubly safe. The only point of using offset is to keep the image data within the limits of the A/D converter so that it doesn't clip the black end of the image. The Zwo recommended offsets don't quite achieve this. Alan

With CMOS cameras, as hardware binning has no advantage over software binning apart from a quicker download time, which can be useful for autofocus, you could set the 2x2 binning gain at 300 (or whatever binning you use for autofocus) on the Control Panel and your 1x1 binning at the gain you normally use for imaging. Offset is not avaiable to be set on the 'Control Panel' as offset is not accessible to programs through Ascom and SGP used Ascom only for device communications. On the Autofocus options panel select 2x2 (or whatever you wish) as the binning so it uses your gain 300 setting. The e-/ADU and read noise settings on the Control Panel are only used to determine the ideal exposure time listed in the Image Statistics panel so don't need to be set if you don't use this feature. As there were many requests for offset to be able to be changed, the SGP team reluctantly modified the program to allow the Zwo native camera driver to be used as an alternative to the Ascom driver. The setting for Zwo native driver offset was put in the Sequencer/Event/Settings panel where it's out of the way of the nornal Ascom settings. As I imagine you normally only image at 1x1 binning for the 1600, I would leave the Control Panel 1x1 gain as not set, and set your most commonly used gain/offset in the Ascom driver itself. Only those events where you actually use a different gain would then have to have their gain/offset settings changed. Personally, as it's easy to forget to set the right gain/offset settings, as they are not easily visible, along with having to have sets of darks for all of these different settings, just use one offset for all gain settings. Take a stack of short exposures 0.5secs or so at the highest gain you'll use and examine the histogram to see if it is black clipped. You'll need to use a higher offset than those 'recommended' by Zwo, as the Zwo offsets do black clip images. The slight loss of dymanic range by using too high an offset at a lower gain is not significant. As han59 says, I also just use unity gain for all exposures as it makes everything so much easier, with only darks needed for different exposure times only. Alan

Hi Ozone, You want the exposure to be short to hopefully freeze the 'seeing' so on the 'Control' section set the camera parameters initially for an exposure of 10mS and unity gain of 135 for the ASI224, gamma off (unticked). Click the 'More' tab and adjust the brightness (camera offset) so that the left edge of the histogram is close to the left edge but not clipped. To get the colour looking about right you'll need to set the Blue gain to about 95 and the Red gain to about 55. You can set the colour gain more accurately by looking at the Moon and adjusting them for a grey image (all three histogram colour bars the same length.) The rest of the 'More' options can be left as they are for the moment. You now need to adjust the exposure and gain to get a bright but unclipped image, with the right hand edge of the histogram around 80% of max. If it's too bright reduce the exposure or reduce the gain. If your exposure is down around 2mS or so reduce the gain to alter the histogram. If it's too dark you can increase the exposure which will reduce your max FPS and possibly make the image less sharp due to the 'seeing' bluring the image. Try increasing the gain to get a brighter image. You can use quite a high gain value where the preview looks very noisy but when stacked the noise is dramatically reduced. If you alter the gain a lot you may need to readjust the brightness setting. On the 'Image' section select Max size to make finding the planet easier and then select a ROI so that the planet fills most of the frame. Leave it at 8 bit capture (don't tick the 16 bit option). If you have debayer icon ticked on the column to the left of the preview window so that you see a colour image you can't select 16 bit anyway. If you record enough frames (more than 50) the 4 bits lost by selecting 8 bit over 16 bit (12 bit really for ASI 224) are recovered anyway (as long as there is noise in the image, which there will be.) Select AVI or SER video format. SER is the preferred Astro format as it allows 16 bit recording and is recognized by most/all stacking programs. The free SER Player is a handy program to preview your SER files and show useful info. Select the arrow to the right of the debayer icon and tick the option 'Temporarily disable debayer' so that you don't debayer while recording, just while previewing. Debayering takes processor time and reduces your FPS. Your stacking program will do the debayering for you. On the 'Capture' section click the 'limit' button to select your video recording duration. Start with 30secs. You can go longer, 2 minutes or more to get more frames but need to be aware of Jupiter's fast rotation which can start blurring a long video when stacked. Saturn rotates more slowly so that isn't such an issue. Under 'Status' check your actual FPS. The 'max' value is limited by your exposure setting. At 10mS max is 1/10mS =100 FPS. With a relatively small ROI you should be getting at least 50FPS, though it depends on your PC hardware speed. Now click the Record button on the 'Capture' section. With a small ROI you hopefully won't run out of RAM before the end of the recording which will cause your FPS to drop right off. If you have an SSD disk installed to record on, the RAM won't be an issue as it can normally write the images to disk as fast as they are being read from the camera. This should get you started. When you get more familiar you can play around with the settings to see if you can improve things a bit more. Alan

Hi Peter, Hope you enjoyed your holiday. Bad luck with the encoder. They are rather delicate. Alan

Remember your maximum FPS achieveable is limited by the reciprocal of the exposure. At 5mS exposure it's 1/0.005 = 200fps. At 20mS it's 50fps, while at 100ms it's 10fps. As you can achieve 30fps full frame on the Sun then exposure was your only limiting factor on the planets, and as Freddie said a smaller ROI would have no effect. Use a higher gain setting to allow a shorter exposure and so achieve a higher frame rate. I've found you can use very high gain settings where the preview looks all noise, but stack enough frames and it 'magically' disappears. A shorter exposure will also give a sharper image if the seeing is poor, as well as higher fps, so enabling more frames to be attained for the same vido duration, which when stacked will mitigate the extra noise introduced by gain. Alan

From the screen shot the autoguider had just reported settling which happens after a sequence has just started, or after a dither, so it doesn't look like a point towards the end of a long sub. At this point the capture is aborted. Do you have the 'Use high speed download' option ticked in the Camera tab of the 'Control Panel' as immediately after the command to switch to normal speed download the Ascom camera driver reported an error and aborts the exposure again but the camera doesn't respond and times out after 4 mins. I'm not sure what exposures it's referring to from your snippet as there was no command to start a new exposure. Try turning off high speed download if it's ticked. This does indicate a camera driver problem. Also, do you have a separate guide scope or an OAG as there is more interaction between SGP and PHD2 with an OAG. I'll have to wait for the full log to try and make more sense of it. Alan

AS2.6.8 is only a 32 bit program so can only access 4GB of memory and you only have 356MB of that left. I run the AS3.0.14 beta which is 64 bit and on my 16GB machine it has claimed 12.2GB for its own use. I've never had any problems with any of the AS3 versions. I think they are all still classed as betas but seem fine. Alan

To clean out the old system files, to free your 30GB, when you run 'Disk Clean up' and have selected Drive C and OK, it runs and displays the non-system files that can be selected and cleared. Click the button 'Clean up system files' and OK and it will run again displaying the additional old system files that can be deleted. You have to scroll down the list and actually tick the system files to delete before it adds them to the total to remove. This will be your 30GB total I expect. I always just tick everything and hit OK. It takes a long time clearing out old system files for some reason, up to 2 hours or more and you may think it's hung up but it will eventually complete the task. I always do this a day or so after a major Windows update when everything seems to be working especially if Drive C is an SSD just to get the disk space back. To date I've never had a reason to regret doing this so soon after the update. Alan

The 3/8" thread is 3/8-16 UNC so 16 TPI. The 1/4" thread is 1/4-20 UNC. Alan

Only GPS receivers with hardware chipsets designed to receive Galileo can use it. Most phones and some recent GPS receivers can receive Galileo alongside GPS (US) and GLONASS (Russia). The receiver in your Meade Dave is very unlikely to be Galileo compatible. Even for new ones I don't know whether Meade would bother implementing re-designed receivers unless the supply of old receiver chipsets dries up, as they would say the accuracy using just GPS is fine for what it's used for. Alan

Glad to help Peter. There should be an option in the camera menu as to whether you save a jpeg along with the raw and what size jpeg. Having the jpeg is useful when showing the folder contents if your OS can't recognize the raw format to provide a thumbnail. The accompanying jpeg is handy then. Alan

To clarify further Relpet your jpeg images will often be reported as 24 bit, which is 3 x 8 bit. This just means that the three colour channels RG and B are each represented with 8 bits. A 24 bit RGB image can display over 16 million different colours (2^24), so a coloured image normally doesn't show significant banding. A mono image (which the moon efectively is) has each of the RG and B components at the same value, so the actual bit depth is then effectively only 8 leading to your problem. If you need to convert your raw images into a format that other programs can read (if they can't read the raw directly) ensure that you choose the output format to be 16 bit. This means 16 bits for each of the RGB components of each pixel so 48 bits in total. If your image is only mono then you can specify this in the conversion and it will create a single mono channel of 16 bit depth from the three colour channels, instead of three identical RGB channels of 16 bits, so your mono image file will only be 1/3 the size of the equivalent colour file. Alan

DSLR Movie mode has the most benefit it you can enable it to use centre cut-out mode. Normally the movie mode down-samples the sensor resolution to HD 1920x1080 or whatever resolution you've selected which also entails chopping off the image top and bottom to fit the 16:9 format. The movie is therefore at a lower resolution that the camera images. In centre cut-out mode the movie uses a 1920x1080 window at the centre of the sensor and therefore no resolution is lost though the apparent FOV is of course much reduced from the full frame image. It looks like a 'zoomed' in image. You generally then need to do a mosaic to image the whole moon. A few Canon cameras had this feature built-in though almost all are able to use it if the 'magiclantern' firmware is installed. I don't believe the Nikon firmware source code is freely available so a similar 'fix' isn't available to my knowledge for Nikon cameras. If you're stuck with only down-sampled full frame movie mode then stacking a series of still frames (RAW not jpeg) would give you a far higher resolution final image. In fact even in centre cut-out mode, the stacked movie image would still be inferior as it is lossy compressed in MOV format anyway. Videos of around 30s (or even less) duration are fine for the moon as 30s at 25fps will give you 750 frames. You normally use a low ISO or gain for the moon as it's so bright, so you aren't going to be struggling with noise, where a large number of frames is beneficial. Your 5 min video file when converted to uncompressed AVI could well be too large to work with if you have limited resources on your computer. I believe that PIPP is able to chop a long video into a series of shorter ones if you wish to try it. Stacking frames from a video won't give you a sharper initial image than a stack of still frames, even if you can use centre cut-out mode, but the lower noise attainable by stacking more images means you can apply more sharpening and other processing features to your final image without the noise becoming too noticeable. Stacking 10 or more (the more the better) still frames would always give you a 'better' higher resolution result than stacking the video. Just a single image may well be better but stacking several images enables the images with better 'seeing' to be used. The above only refers to DSLRs due to lossy movie compression, possible downsampling, and limited frame rate. For dedicated 'planetary' cameras, videos will always give as good or better a result compared to stacking a large number of individual frames, as the videos are lossless and with a small 'region of interest' selectable, a high frame rate is attainable. Videos are just much quicker and simpler to take. Alan

Yes, that's an example of image posterization due to having an insufficient image bit depth. I assume you used the jpeg images from the camera which have a bit depth of only 8 bits rather than using the raw images from the camera which have a bit depth of 14 bits. An 8 bit mono image can only display 256 (2^8) distinct grey levels while a 14 bit image can display 16384 (2^14) distinct grey levels. A smooth brightness gradient will therefore show as a series of grey bands in the 8 bit image. Stretching the image will make the effect more noticeable as the brightness difference between the bands will increase. Also, it appears the image has been sharpened, as the edges between the bands have been accentuated making them even more evident. Alan

Nice image. The faint star extreme top right (µ Ser) looks good along with the three stars in Sagittarius by Saturn. The middle star of the little trio on the top edge above Saturn is 23 Aql and they all look OK too. At least they do after they're downsampled. Alan

An odd one Tom. On the sequencer window does the 'Total Frames Complete' agree with the 'Progress total or does it show one less during the sequence. After the first image does it display 'Downloading' and then fail to display it or does it not even try to download it. I assume you have the latest drivers for the camera installed as failure to download often points to a driver problem. What camera is it? On the Target settings check there are no time constraints ticked which would stop imaging. Unlikely but worth checking. Does this happen with different sequences and did you copy sequence settings between targets? Try making a new sequence from scratch and see if the behavior continues. Examing the SGP log file which covers a problem sequence should shed some light on what's happening. You can post the log file here for others to examine which may help. Logfiles are located in C:\Users\[NAME]\AppData\Local\SequenceGenerator\ Alan

Glad you got the COM ports sorted out Richard and that the Eqmod is now working. Regarding your Wi-Fi problem that has now arisen, I don't have an Eagle 3 so aren't familiar with its way of working. Have you gone through the steps in the manual to setup the wi-fi. It seems it can create its own wi-fi network or connect to an existing one. Hopefully someone who has an Eagle 3 can help you out. If you connect a HDMI monitor and keyboard/mouse to the Eagle 3 you can see what the wi-fi status is. Alan

I have a fairly powerful fan blowing over the camera this time of year to get the temperature down. I usually image at -30C for the ASI1600 and can reach this with an ambient of +15C using the extra fan. Mainly used for taking darks and when it's cloudy as the temperature is normally higher, but I used it when imaging the last couple of times as it could only reach -27C. Using the fan it easily reached -30C at 80% power. If imaging for any length of time you might need to move the fan every couple of hours. Alan

Hi Kirkster501, Using a camera of say 5µm pixels your Meade at 3550mm focal length has an image scale of 0.29"/ pixel so each pixel sees 0.29^2 = 0.08 square arcseconds of sky. The same camera on your refractor at 350mm focal length has an image scale of 3.03"/pixel so each pixel sees 3.03^2 = 9.1 square arcseconds of sky. Each pixel on your refractor sees 9.1/0.08 = 113 times as much sky compared to the Meade so other things being equal would receive 113 times as many photons. However the Meade at 355 mm diameter compared to the refractor at 68mm diameter receives (355^2) / (68^2) = 27.2 times as many photons. Each pixel on the refractor therefore receives 113/27.2 = 4.1 times as many photons as the same sensor on the Meade so needs about a quarter of the exposure time of the Meade for the same image brightness on the sensor. The image on the refractor's sensor will of course be far smaller that that on the Meade's sensor so will show far less detail. I think that's right unless my sums have let me down. Alan

To clean the concrete dust out of the holes drilled in my pier I just used a piece of tubing that fits down the hole and joined the the other end to a vacuum cleaner nozzle with some duct tape. You get great suction with the small diameter tubing and the dust disappears without it being blown everywhere. Alan

Just to add COM ports 1 and 2 are quite likely used by the actual hardware serial ports on the motherboard even if they are not actually wired to be used. Latest motherboards may only have 1 COM port on the motherboard so COM 2 may be available but it's normal practice for user defined COM ports to start at COM 3. Someone who actually has an Eagle 3 could confirm this. Alan

The find COM port in Eqmod doesn't always work properly and I'm not sure if it checks (or works) for ports above COM port 8. It seems you have a lot of COM ports that are not available to use due to them not being released properly when a USB device is unplugged. In device manager expand the PORTS section and from the top menu bar select 'View\Show Hidden Devices'. A lot of greyed out COM ports should appear. If you right click a greyed out COM port entry and select 'Uninstall device' it should free up that COM port for use by other devices. Free up all the greyed out ones if you wish as it won't cause any problems. Your Eqmod COM port is remembered by the Eqmod device so you'll have to manually change it to a lower COM port number. Right click the device manager COM port entry for your Eqmod device and select 'Properties\Port Settings\Advanced'. Under COM port number select one of the now available lower COM port numbers (8 or below) and click OK (twice). The device manager Eqmod COM port should have changed. On the Eqmod settings page select this new COM port number and it should now work OK. If you're not sure which is your Eqmod device in Device manager, just unplug and re-plug your Eqmod USB connector and see which entry disappears and reappears. I hope this helps you out. Alan

During the day you may need to go to 1/500 or 1/1000 exposure when looking at the sky on liveview or it will still be overexposed I expect. Alan

For live view the exposure is always very short, with a fraction of a second being the longest, so setting a long liveview exposure doesn't give you a more 'exposed' image. It only simulates a long exposure up to a point by increasing the gain. Very short exposures will influence the live view if it's within the live view exposure range. It's best to use ISO to adjust the liveview 'exposure'. When you select liveview in APT I believe it automatically switches to the highest ISO setting, so you may need to reduce the ISO to a lower value (after you've selected liveview) to get a better exposed view. For liveview moonshots as David says, use ISO 100 or 200, and an exposure of around 1/50 or so. Alan