View Full Version : FX1 vs PD170?


Rafael Lopes
April 16th, 2006, 12:38 AM
Hi,

I have to shoot a bunch stuff for a producing company and in a lot of different indoors places (one of them is a mine). And due to the short time until the due date and the geographical longitude between each location I'm not sure there'll be time to visit each place before the shots. I have a FX1E that I was planning to use (even though they don't need HD I have a lot to gain by shooting Hd and downsizing it to SD) but when they told me about the possibilities of bumping into low light conditions in some of these places the PD170 came to mind (they have a bunch of PD170 and PD150 that they said I could use). Is it justifiable to shoot with the PD170 (1 lux) over the FX1 (3 lux)?.

Robert Young
April 16th, 2006, 12:48 AM
I have a PD 170 and a Sony A1 HDV. The PD 170 is one of the best low light cameras on the market. A1, FX, Z1 are not as good in low light. If the project is 4:3 DV out, you will be better off with the PD 170. If it's 16:9, you may get better images with FX/Z1 with the "hypergain" on. The Sony HDV cams are all native 16:9 and they make beautiful images.

Dylan Pank
April 16th, 2006, 04:46 AM
if you've not seen hypergain on the Z1, its the grainiest image you can imagine. Think of super8 reversal cross processed and pushed two stops in processing!

Also, only the Z1 has hypergain.

Marcus Marchesseault
April 16th, 2006, 05:25 AM
I've worked with both and you need about 4-6 times as much light (2-3 f-stops) to light for the FX1 than the PD170. I like both cameras, but if there is no need for the HDV, the PD170 will be better. Heck, bring both cameras! :)

Boyd Ostroff
April 16th, 2006, 07:27 AM
I've worked with both and you need about 4-6 times as much light (2-3 f-stops) to light for the FX1 than the PD170.

That doesn't match my experience. True, the PD-150 will give you a little edge in low light but certainly not 3 or even 2 stops IMO. I have a VX-2000, a PDX-10 and a HVR-Z1. I did some testing and the PDX-10 is 2.5 f-stops slower than the VX-2000. The Z1 is clearly better in low light than the PDX-10, so I would say it's 1.5 f-stops slower than the VX-2000. However you do have a very clean gain boost on the Z1 (and FX1) so I'd think the real world difference would be more like 1 stop. But I'd agree that the hypergain probably isn't the way to go, and since you don't have a Z1 it's not an issue anyway. Now my experience is with the VX-2000, and I know they improved the quality of the gain boost on the PD-170 so that might tilt the scales a bit.

Since you're working in SD you could lower the FX1 shutter speed to 1/25 and pick up another f-stop which should make things relatively equal. You can do this on the FX1 without any quality loss in SD mode or downconversion, as opposed to cameras like the PD-170 which cut your vertical resolution in half at shutter speeds less than 1/50.

The low light issue has been discussed a lot. See the following thread: http://www.dvinfo.net/conf/showthread.php?t=54414. Also see this for more discussion of the PD-170 vs the FX1: http://www.dvinfo.net/conf/showthread.php?t=50112

Rafael Lopes
April 17th, 2006, 05:24 AM
That doesn't match my experience. True, the PD-150 will give you a little edge in low light but certainly not 3 or even 2 stops IMO. I have a VX-2000, a PDX-10 and a HVR-Z1. I did some testing and the PDX-10 is 2.5 f-stops slower than the VX-2000. The Z1 is clearly better in low light than the PDX-10, so I would say it's 1.5 f-stops slower than the VX-2000. However you do have a very clean gain boost on the Z1 (and FX1) so I'd think the real world difference would be more like 1 stop. But I'd agree that the hypergain probably isn't the way to go, and since you don't have a Z1 it's not an issue anyway. Now my experience is with the VX-2000, and I know they improved the quality of the gain boost on the PD-170 so that might tilt the scales a bit.

Since you're working in SD you could lower the FX1 shutter speed to 1/25 and pick up another f-stop which should make things relatively equal. You can do this on the FX1 without any quality loss in SD mode or downconversion, as opposed to cameras like the PD-170 which cut your vertical resolution in half at shutter speeds less than 1/50.

The low light issue has been discussed a lot. See the following thread: http://www.dvinfo.net/conf/showthread.php?t=54414. Also see this for more discussion of the PD-170 vs the FX1: http://www.dvinfo.net/conf/showthread.php?t=50112

So, basicaly what you are saying is that by SPECIFICLY shooting with a 1/25 shutter I can make up for the different low-light performance of each camera, therefore making them equal in low light?

Boyd Ostroff
April 17th, 2006, 06:05 AM
No, I'm saying that the default shutter speed on the PD-170 would be 1/50. If you lower its shutter to 1/25 it uses "field doubling" which means the same data is written to each of the interlaced fields, resulting in a 50% loss of vertical resolution. This is why one generally avoids shutter speeds lower than 1/50 on the PD-170.

The FX1 also uses field doubling at 1/25 sec, but it's done at high definition resolution (1920x1080) before downsampling to 720x576. This means that hardly lose any vertical resolution on the FX1 while shooting at 1/25. So it's another way you can help compensate for the FX1's lower sensitivity in dark places.

It may not always be appropriate, but it could come in handy sometimes.

Rafael Lopes
April 17th, 2006, 07:02 AM
Ah, ok. Big thanks to everybody for the help. I'll probably go with the pd170. I had no idea the resolution loss under 1/50 was so agressive. One more thing, I can choose if I want to shoot DVCAM or regular DV, right? I still have to check if my pc supports DVCAM via firewire. I have premiere pro 2.0 and I know it has a lot of presets (I think I saw a preset for the pd150 but I don't know if it'll work the 170 or if it for dvcam or plain dv), but since I always use the FX1 I never checked.

Boyd Ostroff
April 17th, 2006, 07:40 AM
DVCAM and regular DV are completely identical in terms of data so you don't need to change anything. There is no quality difference with DVCAM, the 1's and 0's are exactly the same. The only difference is in how that data is written to tape. The DVCAM tapes run faster so you only get 40 minutes recording time on a 60 minute tape. There are a few other differences in the recording format, but you don't really need to be aware of them because they won't affect anything in terms of capture or editing.

Rafael Lopes
April 17th, 2006, 08:16 AM
I knew that dv and dvcam were the same while you film but I was not sure if something different was needed to capture or edit dvcam. I'll ask the company to keep the pd170 some time ahead to get used to it. Any other useful advise?

Matt Davis
April 17th, 2006, 03:41 PM
Any other useful advise?

The Z1/FX-1 can shoot at HDV with +9dB gain and get away with it when downsampled to SD - but ignore the mention of HyperGain. <g>

Boyd mentioned the 1/25 trick - again shooting HDV and using downsampled DV - and I can confirm this DOES work.

In fact, when you put the two together, it seems to match my old PD150 (not quite a PD170). I've not needed an on-camera light yet! :)

On a slightly different tack, the standard image setup on the Z1/FX-1 will match a PD150 very well, especially if you can stick to the default white balance settings. However, once you've found your Picture Profile setting of choice, it can be a shock to go back to 'unstretched black' and ringing around edges! :-D

I don't miss my PD150 at all.

HTH.

Marcus Marchesseault
April 17th, 2006, 10:02 PM
I realized my earlier post was too brief. I think I mixed up this thread with another. I forgot to add that the FX1 is FAR superior in every way to the PD170 but one - low light performance. The FX1 is actually quite good compared to any other camera in low-light but the PD/VX or cams with larger chips. The mention of shooting in a mine is what made me decide to recommend trying the PD170. I still say bring both since they are at your disposal. A PD170 isn't so large that it will be a burden to bring unless you are hiking great distances.

I think a MUCH more important factor (considering both cameras are appropriate) is which camera you are accustomed to working. If you have never used the PD170 and you have hundreds of hours behind the FX1, that's a no-brainer. I'm guessing the mine workers have tons of battery-operated light, so the FX1 will probably be just fine. You might not even need gain, nevermind slow-shutter. I lit a scene for the FX1 with the equivalent of 350Watts of light (actually 100W of fluorescent) and much of that was lost to snoots and such. A single 100W on-cam light can do news-style lighting with probably no gain needed. Miners must supply all of their own light, so you will have lots of practicals keeping your scene bright. You might not even need your own light, but bring some anyway. A battery belt and a light or two isn't really inconvenient.

There is no substitute for good lighting technique. The PD170 needs less light so you can use smaller lights and be more portable. The FX1 can look just as good if stronger lights are used. Use the camera that fits YOU the most and you will get the best results.

Rafael Lopes
April 18th, 2006, 01:52 AM
Thanks guys! I'll be doing some testing with both cameras and I'll try to visit at least the darkest of all 10 locations to be prepared. Actualy I'll try to find time to visit them all and I'll bring my FX1 with me...if I come to the conclusion that I'll need a more low light capable camera I'll come back with the PD170.