Downconvert while capturing or later? at DVinfo.net

Frank Spangler · February 11th, 2007, 06:21 PM

I have just ordered a Canon XH A1 and now I have some questions about editing the footage that I shoot. Most of my clients will still need a SD product in the end, and I understand that you can have this camera downconvert to SD while you are capturing.

I use Edius Pro 4.03 for the most part...

My question is, what are there advantages of capturing and converting to Canopus HQ, editing in that environment, and then down converting to SD in the end, over simply capturing a SD signal output by this camera and editing that. Has any one compared the results?

If there is not a lot of difference it seems that the SD signal would be a lot easier to work with and a lot easier on storage...

Richard Hunter · February 11th, 2007, 08:13 PM

Quote:

Originally Posted by Frank Spangler

I have just ordered a Canon XH A1 and now I have some questions about editing the footage that I shoot. Most of my clients will still need a SD product in the end, and I understand that you can have this camera downconvert to SD while you are capturing.

I use Edius Pro 4.03 for the most part...

My question is, what are there advantages of capturing and converting to Canopus HQ, editing in that environment, and then down converting to SD in the end, over simply capturing a SD signal output by this camera and editing that. Has any one compared the results?

If there is not a lot of difference it seems that the SD signal would be a lot easier to work with and a lot easier on storage...

Hi Frank. You are correct that you can downconvert at capture or after editing. If you are going to DVD in the end, please be aware that downconverting at capture will mean going through 2 colourspace conversions (4.2.0 to 4.1.1 at capture, and 4.1.1 to 4.2.0 when encoding for DVD).

In addition to the options you mention, you can also edit the HDV files on the Edius timeline (with a suitable PC). This means you do not have the large HD requirements of the HQ codec as the HDV files are similar in size to SD DV. However, the realtime playback performance is more restricted with HDV and the rendering times are also longer.

So overall, there is a difference in quality between the different methods, but whether the benefits of HDV editing outweigh the disadvantages depends in part on the type of editing you do, and the results you are looking for. I suggest you take a (short) sample project and compare the different results for yourself.

Richard

Philip Hinkle · February 11th, 2007, 10:18 PM

Is the quality of the in-cam downconversion quality better than regular SD from a PD/VX or GL2 type of cam. I can understand how the quality of importing in HQ and downconverting after the edit will be better but I don't have the storage space for that workflow yet. If the quality is better than regular SD I will probably live with incam downconverting.

Just wondering.

I just ordered an A1 as well but have been reading here for a few weeks and am armed with information to optimize my experience when I get it...thanks to everyone.

James Binder · February 12th, 2007, 02:47 AM

(Sorry, don't mean to hijack the thread here!)

As someone who is getting ready to purchase an A1, I’m very curious about this question as well.

I produce mostly corporate video and deliver my projects in standard def – via my trusty XL1s, which I’ve shot for years now. Will I see any quality improvement shooting HD and either down converting (on capture) or editing in HD and rendering to standard def?

If so, and as asked above, which method produces better results?

And finally… since I am ultimately going to standard def – will the quality of the A1 (in the final analysis) be superior to the XL1s?

Thanks --

Mark Fry · February 12th, 2007, 09:12 AM

Quote:

Originally Posted by Philip Hinkle

Is the quality of the in-cam downconversion quality better than regular SD from a PD/VX or GL2 type of cam.

Yes, it is. My experiments with down-converting from the XH-A1 look a little better than XM1, XM2 (PAL versions of GL1 & GL2) or VX2100. I am quite familiar with these cams, since I have used an XM1 for 6 years, and used footage from friends' XM2 and VX211 cams in my productions. I have viewed the SD results from the XH-A1 on various SD CRT televisions and also on some widescreen, HD-ready LCD sets. I couldn't put my finger on what the difference is exactly, but when viewed back-to-back, I notice an improvement.

Just one point: The XH-A1 (like all HDV cams) shoots true widescreen. I'm not sure about the VX2100, but the XM/GL cams do not. This may or may not be an advantage, depending on whether you need to mix footage from the different cameras. I'm going to have to be very careful...

I can see that this might not be the case for NTSC versions, since HDV and PAL DV use 4:2:0 colour sampling whilst NTSC DV uses 4:1:1, as mentioned above, but other people have posted that down-converted HDV is better than NTSC DV.

This was an important consideration for me before deciding to take the plunge with HDV. It will be a while before I will upgrade my PC and software to edit HDV, and probably rather longer before there's any demand for my stuff on high-def DVD. As it is, I have the immediate benefit of better looking SD pictures whilst building up an archive of high-def footage.

Brad Tyrrell · February 12th, 2007, 09:22 AM

I jumped from the XL-1 to the A1 a couple of months ago and gradually converted workflow to editing in HDV. There always seems to be more hassle than you plan on in any upgrade so I did it piece at a time. First downconverted in camera then upgraded the NLE (Premiere Pro 2), the encoder (Tmpgenc), processor/ram, - still working on getting a widescreen HD monitor.

I found the A1 camera downconvert footage better that the XL-1. First attempts at editing in HDV were dissappointing since I used Adobe's resizing and compressing options for SD mpeg for DVD. Those results worse than the XL-1. I tried the Cineform Aspect HD trial for a bit. The image was a little softer but much easier to edit. I just don't do heavy-duty editing so I eventually opted to pass on that $500. (Waiting to see what Adobe's fixes are this summer)

I used the trial version of Tmpgenc and liked it a lot. Lancosz3 resize filter and 2 file output that Encore2 likes. Using that now.

I capture to a laptop (not very high end) using HDVSplit. Split doesn't currently "split" from A1 capture but captures fine. There's an occasional audio sync problem that I don't understand but easily fixable in Premiere (or in Tmpgenc for that matter). It's not a progressive thing like with old Premiere captures where the audio drifted farther and farther the longer the clip, - that was tricky to fix. It's more a constant offset, - annoying but much easier to handle. There's probably some switch I just haven't found yet.

Everyone is pretty much going to have to switch to some version of HD, - can't have customers able to get a better picture with their hand-helds. HDV is probably the most cost effective way, and the A1 is a beautiful machine.

February 11th, 2007, 06:21 PM	#1
Frank Spangler New Boot Join Date: Jan 2006 Location: Berrien Springs, MI (Now spending most of my days in Vietnam) Posts: 24	Downconvert while capturing or later? I have just ordered a Canon XH A1 and now I have some questions about editing the footage that I shoot. Most of my clients will still need a SD product in the end, and I understand that you can have this camera downconvert to SD while you are capturing. I use Edius Pro 4.03 for the most part... My question is, what are there advantages of capturing and converting to Canopus HQ, editing in that environment, and then down converting to SD in the end, over simply capturing a SD signal output by this camera and editing that. Has any one compared the results? If there is not a lot of difference it seems that the SD signal would be a lot easier to work with and a lot easier on storage... __________________ Frank Spangler Video Production: www.panopro.com Stock Images: www.worldviewimages.com Stock Video: www.pond5.com

February 11th, 2007, 10:18 PM	#3
Philip Hinkle Regular Crew Join Date: Jun 2004 Location: Stoughton, WI Posts: 169	Adding to Franks original question Is the quality of the in-cam downconversion quality better than regular SD from a PD/VX or GL2 type of cam. I can understand how the quality of importing in HQ and downconverting after the edit will be better but I don't have the storage space for that workflow yet. If the quality is better than regular SD I will probably live with incam downconverting. Just wondering. I just ordered an A1 as well but have been reading here for a few weeks and am armed with information to optimize my experience when I get it...thanks to everyone.

February 12th, 2007, 02:47 AM	#4
James Binder Major Player Join Date: Jan 2005 Location: NY, NYC Posts: 367	(Sorry, don't mean to hijack the thread here!) As someone who is getting ready to purchase an A1, I’m very curious about this question as well. I produce mostly corporate video and deliver my projects in standard def – via my trusty XL1s, which I’ve shot for years now. Will I see any quality improvement shooting HD and either down converting (on capture) or editing in HD and rendering to standard def? If so, and as asked above, which method produces better results? And finally… since I am ultimately going to standard def – will the quality of the A1 (in the final analysis) be superior to the XL1s? Thanks --

February 12th, 2007, 09:22 AM	#6
Brad Tyrrell Major Player Join Date: Oct 2003 Location: Morristown, New Jersey Posts: 249	I jumped from the XL-1 to the A1 a couple of months ago and gradually converted workflow to editing in HDV. There always seems to be more hassle than you plan on in any upgrade so I did it piece at a time. First downconverted in camera then upgraded the NLE (Premiere Pro 2), the encoder (Tmpgenc), processor/ram, - still working on getting a widescreen HD monitor. I found the A1 camera downconvert footage better that the XL-1. First attempts at editing in HDV were dissappointing since I used Adobe's resizing and compressing options for SD mpeg for DVD. Those results worse than the XL-1. I tried the Cineform Aspect HD trial for a bit. The image was a little softer but much easier to edit. I just don't do heavy-duty editing so I eventually opted to pass on that $500. (Waiting to see what Adobe's fixes are this summer) I used the trial version of Tmpgenc and liked it a lot. Lancosz3 resize filter and 2 file output that Encore2 likes. Using that now. I capture to a laptop (not very high end) using HDVSplit. Split doesn't currently "split" from A1 capture but captures fine. There's an occasional audio sync problem that I don't understand but easily fixable in Premiere (or in Tmpgenc for that matter). It's not a progressive thing like with old Premiere captures where the audio drifted farther and farther the longer the clip, - that was tricky to fix. It's more a constant offset, - annoying but much easier to handle. There's probably some switch I just haven't found yet. Everyone is pretty much going to have to switch to some version of HD, - can't have customers able to get a better picture with their hand-helds. HDV is probably the most cost effective way, and the A1 is a beautiful machine.