www.astrocafe.hk

The new DMK 51 got nothing special in terms of operation, but a larger sensor size. I expect it can do a full solar disc imaging with LS80T (f=560mm) without drifting. Indeed, it does, see the attached photo. However, if you want to image the prominences and there are big prominences, one needs to rotate the cam so that the shorter side of the sensor can capture all the prominences. Of course if there are too many prominences around the sun, there is no way help. In practice, I never encounter such case before. So if one wants to make a composite photo of solar disc and prominence, do image the prominence first. Get the camera oriented properly during prominence imaging and then the solar disc afterward. This eases the post processing.

好像影像質量一般，細節有點粗，視寧度不太好? 好像我用DMK41+APM 80/480 + LS75F的效果還是好些

今天地球處於遠日點，所以DMK51配LS80T的560mm是可以，但剛好而已，LS60T會空間大些。

No! The images were not taken in yesterday, but 28-6-2012 (look at the file's time stamp). As u mentioned that the eccentricity is 0.0167.
viewtopic.php?f=7&t=3137
After simple calculation, the visual size of sun disc at Perihelion will increase not more than about 3.3% compare with that of Aphelion. The DMK 51 is able to image full disc at Perihelion, although the margin is smaller.
About the images, I am still learning how to process solar images. I feel bad about the composite solar image. This is exceptionally bad!

willis 寫:About the images, I am still learning how to process solar images. I feel bad about the composite solar image. This is exceptionally bad!

很高興你不是頼個天....

你當我是誰？行為藝術博士？我習慣自我完善，不會頼天頼地！

我訂了兩枝鏡回來，一枝是2/3"片幅，另一枝是1/2"的，可以用來裝在DMK51上做全天魚眼鏡：

http://www.fujifilmusa.com/products/opt ... index.html

這個測試不俗的：

http://www.astrosurf.com/cavadore/techn ... index.html

See if this lens is better than Peleng 8mm.

兩者是不同片幅的，Peleng是用在全片幅上，而Fujinon則是CCTV，後焦點也只有數毫米。

到了，Willis快點還相機，我要試鏡

viewtopic.php?f=20&t=1389&p=20465#p20465

我月底要去美國10天參加國際天文館會議，到時借Atik電動濾鏡盤及Baader 1.25" IRGB濾鏡組給你，那四片小濾鏡要近三千元，RG之間有區間可以濾去Sodium light這條光害中最強的光譜的，到時拍些RGB深空吧