Mosaic of entire moon - 7th Nov

[naskies (Dave)]

I wanted to make large prints of the moon, but unfortunately my 924 mm focal length refractor + Canon 5DmkII combo only gives me a 1300 pixel wide image of the moon.

I decided to use a 5x PowerMate in order to capture the moon as a mosaic of six panels. Although capturing in movie mode, stacking and processing with wavelets would have been ideal, by my calculations I would have needed about 60 panels - too impractical for me. Instead, I captured 50 still frames for each panel, hand picked the best one for each panel, and merged the final six still frames in Photoshop.

The end result is that I now have a 6600 pixel wide image of the moon that looks fantastic as a 61x61 cm print. I've attached a downsized version and a 100% crop, but if you have a high resolution monitor the full 7500x7500 pixel image can be downloaded here:

http://itee.uq.edu.au/~davel/_temp/Moon-Large-Print.jpg (16.5 MB)

It's obviously nowhere near the true/effective resolution of Dennis' magnificent efforts, but I'm pretty happy with the end result for my wall


Dave

[Dennis]

Nice work Dave!

Just for comparison, here is a single, raw, unprocessed frame from the 2000 frame avi (grabbed via VirtualDub), showing the view at 5800mm focal length and the 8-bit image tonality of the 1024x768 pixel image.

I think the chip size is 5.80mm × 4.92mm with a unit cell size of 4.65μm × 4.65μm.

Cheers

Dennis

[naskies (Dave)]

Thanks Dennis - and for posting your raw frame. The seeing was bad when I shot these, so I had to bump up the shutter speed and ISO setting (3200) unfortunately.

I'll have to give the video mode a go sometime. Have you put together a full-moon mosaic? It would be an amazing print with the resolution and clarity of your work.

[iceman (Mike)]

Nice project, Dave! Looks good!

[El Paso Eric (Eric)]

Great project, Dave. I love doing Mosaics of deep sky targets.

I did a little playing in CS3. The image responds well to a little noise filtering and a light High Pass filter.

What printer did you use for printing this image?

[naskies (Dave)]

Thanks Mike & Eric!

Eric - thanks for the high pass filter suggestion; I hadn't thought of that. I normally use unsharp masking with large radius (e.g. 20%, 20 px, 0) as a contrast booster for prints - in combination with strong background blur (bokeh) it gives an eye catching 3D effect.

I didn't remove the noise as I've found that single colour tone images tend to print better with noise at large sizes. Cloudless sunsets shot with low ISO are often a pain to enlarge without causing obvious banding or pixellation (noise helps give a poor man's dithering effect).

My printer is a Canon iPF6100, i.e. it's a 24 inch wide format pigment inkjet that takes roll paper. They're amazing beasts - it took less than 10 mins to wake itself up from sleep mode, load the paper, print the photo, cut the photo from the roll, clean itself up, and eject the roll. All without me having to touch it (except for removing a dust cover)!

[El Paso Eric (Eric)]

A little OT, sorry...
Thanks for the printer info, Dave. When i was working my Corporate job, I had access to an HP800 (42" wide). I had printed some excellent large prints on that. But now, I have to farm out the work. I've been thinking of purchasing a large format printer for my home engineering office and to print my deep sky prints. I've been reading that the 10 & 12 color units are much better at printing blacks and greys, for some of my H-alpha shots.

[naskies (Dave)]

No worries... I love talking printers! Epson and Canon appear to be the main players these days. I chose Canon in the end because they're reputed to have far less nozzle clogging issues (but Epson have slightly better colours, I'm told).

The print quality is amazing with the 10+ colour inks when matched with the right paper and tuned for the viewing environment. I'm super impressed with the depth of blacks and tonality of B&W prints... especially on quality matte paper such as Museo Portfolio Rag that has no visible reflections at all indoors. I use pigment inks which along with the paper are meant to be archival (rated for 100-200 years) - I have many prints that have been in direct sunlight every afternoon for the past nine months, and they still look newly printed. I also print on canvas, banners (vinyl-like material), and plain paper technical charts for my consulting work.

The printer companies make most of their profits off consumable media/ink so the printer itself can fluctuate wildly in price. For example, I bought my iPF6100 on rebate for only $1399 USD in February this year... bargain. However, if you get a large enough unit (e.g. 17 inch or wider) then the consumable costs are pretty cheap. My consumable costs are less than $2.50 per square foot for paper, ink, and maintenance. This is about 15% of the local commercial rates on similar media, so it's very economical for me.

Downsides are that there's a steep learning curve involved, and it's fairly labour intensive to get everything profiled and tweaked correctly. The upfront cost is also rather steep to get economies of scale for consumables, i.e. the initial printer purchase, buying inks in large tanks, paper in 50 feet rolls, ink/paper profiling, configuration mistakes, etc.

Overall, I can highly recommend them. If you can afford the set up cost and have the room for them, I'd recommend getting a 40 inch+ wide printer... that's my only regret, and one that I hear commonly from other 24 inch printer owners. If you're in the market for one, I can recommend talking to someone at Shades of Paper ( http://www.shadesofpaper.com ) - incredible service and prices (negotiate with them).

[El Paso Eric (Eric)]

Thanks Dave. I'll check out Shades of Paper. I recall that the ink cost of the HP800 was very reasonable. They were large volume cartridges and yet were less expensive than most desktop cartridges.

I'm not really opposed to the higher capital cost, its the $70USD per cartridge that is the real killer, especially at 10 or 12 units per printer. The Ink tanks on the HP800 used to last quite a long time, even with full coverage images.

I keep my monitor calibrated and have the profile handy (sending to local printers). But I still would like to have the control in my hands.

Any specific 36 or 42" units you can recommend?

Again, sorry for hijacking the thread...

Eric